Systems for communicating using multiple frequency bands in a wireless network

ABSTRACT

Communication signals using a first and a second frequency band in a wireless network is described herein. The first frequency band may be associated with a first beamwidth while the second frequency band may be associated with a second beamwidth. An apparatus may include receiver circuitry arranged to receive first signals in a first frequency band associated with a first beamwidth and second signals in a second frequency band associated with a second beamwidth, the first signals comprising a frame synchronization parameter and the second signals comprising frame alignment signals. The apparatus may further include processor circuitry coupled to the receiver circuitry, the processor circuitry arranged to activate or deactivate the receiver circuitry to receive the frame alignment signals based on the frame synchronization parameter. Other embodiments may be described and/or claimed.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a continuation-in-part of co-pending U.S.patent application Ser. No. 12/685,607, filed Jan. 11, 2010, whichclaims priority to U.S. patent application Ser. No. 11/394,572 filedMar. 31, 2006, which claims priority to U.S. Provisional PatentApplication No. 60/730,575, filed Oct. 26, 2005, and to U.S. patentapplication Ser. No. 11/394,600 filed Mar. 31, 2006, which claimspriority to U.S. Provisional Patent Application No. 60/730,574, filedOct. 26, 2005. The specifications of these applications are herebyincorporated by reference.

TECHNICAL FIELD

Embodiments of the present disclosure relate to the field of datacommunication, more specifically, to data communication in a wirelessnetwork.

BACKGROUND

In the current state of wireless communication, an increasing number ofcommunication devices are able to wirelessly communicate with eachother. These communication devices include a variety of devices havingmany different form factors varying from personal computers, mobile ordesktop, displays, storage devices, handheld devices, telephones, and soforth. A number of these communication devices are packaged as “purpose”devices, such as set-top boxes, personal digital assistants (PDAs), webtablets, pagers, text messengers, game devices, smart appliances, andwireless mobile phones. Such devices may communicate with each other invarious different wireless environments such as wireless wide areanetworks (WWANs), wireless metropolitan area networks (WMANs), wirelesslocal area networks (WLANs), and wireless personal area networks(WPANs), Global System for Mobile Communications (GSM) networks, codedivision multiple access (CDMA), and so forth.

The growing demand for high throughput applications such as videostreaming, real-time collaboration, video content download, and thelike, imposes stringent requirements on wireless communications toprovide better, faster, and lower cost communications systems. In recentyears, unlicensed frequency bands such as 2.4 GHz (Industrial,Scientific, Medical (ISM)) and 5.0 GHz (Universal National InformationInfrastructure (UNII)) bands have been utilized for communications up tofew hundred Mbps. To achieve these bit rates, relatively complexmodulation techniques such as multiple-input/multiple-output (MIMO)orthogonal frequency division multiplexing (OFDM) have been proposed tothe Institute of Electrical and Electronics Engineers (IEEE). Due to thepopularity of the ISM and UNII bands, these bands are becoming crowdedresulting in substantial interference for users of these bands.

To provide an interference limited Gbps communications, IEEE committeeshave recently begun looking at communications at higher frequencies suchas frequency bands greater than 20 GHz. FIG. 1 shows the currentlyavailable unlicensed frequency bands in selected major industrializedcountries/regions.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present disclosure will be readily understood by thefollowing detailed description in conjunction with the accompanyingdrawings. To facilitate this description, like reference numeralsdesignate like structural elements. Embodiments are illustrated by wayof example and not by way of limitation in the figures of theaccompanying drawings.

FIG. 1 illustrates currently available unlicensed frequency bands inselected major industrialized countries/regions;

FIG. 2 illustrates exemplary beamwidths of different frequency bandsusing antennae with about the same aperture size;

FIG. 3 illustrates a wireless network in accordance with variousembodiments;

FIG. 4 illustrates various types of CSMA/CA protocol data that may betransmitted and/or received using a first and a second frequency bandsin accordance with various embodiments;

FIG. 5 illustrates a process for communicating by a communication devicein a wireless network in accordance with various embodiments;

FIG. 6 illustrates a communication device in accordance with variousembodiments;

FIG. 7 illustrates a circuitry for transmitting and receiving signalsusing two frequency bands in accordance with various embodiments;

FIG. 8 illustrates a frame format in accordance with variousembodiments;

FIG. 9 illustrates another frame format in accordance with variousembodiments;

FIG. 10 illustrates yet another frame format in accordance with variousembodiments;

FIG. 11 illustrates two frame formats using two frequency bands of asoft coupled system adapted to communicate using the two frequency bandsin accordance with various embodiments;

FIG. 12 illustrates a circuitry of a soft coupled system adapted tocommunicate using two frequency bands in accordance with variousembodiments;

FIG. 13 illustrates another process for communicating by a communicationdevice in a wireless network in accordance with various embodiments;

FIG. 14 illustrates yet another process for communicating by acommunication device in a wireless network in accordance with variousembodiments;

FIG. 15 illustrates a search procedure by a communication device in awireless network in accordance with various embodiments;

FIG. 16 illustrates an antenna adjustment/link establishment procedureby a communication device in a wireless network in accordance withvarious embodiments;

FIG. 17 illustrates another antenna adjustment/link establishmentprocedure by a communication device in a wireless network in accordancewith various embodiments;

FIG. 18 illustrates a signal reception procedure by a communicationdevice in a wireless network in accordance with various embodiments;

FIG. 19 illustrates a communication system using a coordinating devicein accordance with various embodiments;

FIG. 20 illustrates a process for coordinating communication by acoordinating device in a wireless network in accordance with variousembodiments; and

FIG. 21 illustrates a process for coordinating communication by acommunication device in a wireless network in accordance with variousembodiments.

FIG. 22 illustrates a communication system with two different types ofwireless communication systems.

FIG. 23 illustrates exemplary user equipment suitable for use with twodifferent types of wireless communication systems.

FIG. 24 illustrates a timing diagram with a frame synchronization periodcommon for two different types of wireless communication systems.

FIG. 25 illustrates a timing diagram to synchronize frames from twodifferent types of wireless communication systems using a framesynchronization period.

FIG. 26 illustrates an operating environment to detect frame alignmentsignals using a frame synchronization period.

FIG. 27 illustrates a process for controlling a wireless receiver todetect frame alignment signals using a frame synchronization period.

DETAILED DESCRIPTION

In the following detailed description, reference is made to theaccompanying drawings which form a part hereof wherein like numeralsdesignate like parts throughout, and in which is shown by way ofillustration embodiments in which subject matter of the presentdisclosure may be practiced. It is to be understood that otherembodiments may be utilized and structural or logical changes may bemade without departing from the scope of the present disclosure.Therefore, the following detailed description is not to be taken in alimiting sense, and the scope of embodiments in accordance with thepresent disclosure is defined by the appended claims and theirequivalents.

Various operations may be described as multiple discrete operations inturn, in a manner that may be helpful in understanding embodiments ofthe present disclosure; however, the order of description should not beconstrued to imply that these operations are order dependent.

The description may use phrases such as “in one embodiment,” or “invarious embodiments,” which may each refer to one or more of the same ordifferent embodiments. Furthermore, the terms “comprising,” “including,”“having,” and the like, as used with respect to embodiments of thepresent disclosure, are synonymous.

According to various embodiments of the present disclosure, methods andsystems are provided in which a communication device communicates withother communication devices in a wireless network using a first and asecond frequency band. For the embodiments, the first frequency band maybe associated with a first beamwidth while the second frequency band maybe associated with a second beamwidth, the first beamwidth being greaterthan the second beamwidth. Although the following description describesusing two frequency bands, in alternative embodiments, more than twofrequency bands may be employed.

In various embodiments, the first frequency band may be employed tocommunicate (i.e., transmit and/or receive) first signals to facilitateinitial communication between the communication device and the othercommunication devices of the wireless network, including initialcommunication of first signals containing signals and/or controlinformation for coarse configuration of the other communication devicesto wirelessly communicate with the communication device. The subsequentcommunication of second signals between the devices may be transmittedusing the second frequency band. The second signals further includesignals and/or control information for finer configuration of the othercommunication devices to wirelessly communicate with the communicationdevice.

In some embodiments, the first signals may be adapted for signaldetection, initial beam forming, and/or initial carrier frequency offset(CFO) estimation, to facilitate subsequent communication using thesecond frequency band. The second signals communicated through thesecond frequency band may be adapted for more precise beam forming thatsupplements the initial beam forming and/or signals that are adapted forfine CFO estimation that may supplement the initial CFO estimation. Thesecond signals may further facilitate timing synchronization of theother communication devices to the communication device. The secondsignals communicated using the second frequency band, as previouslyalluded to, may facilitate further communication using the secondfrequency band in order to facilitate the communication of third signalsusing the second frequency band. The third signals to be communicatedusing the second frequency band may include various types of dataincluding, for example, data relating to video streaming, realtimeand/or non-realtime collaboration, video content download, audio andtext content download and/or upload, and so forth.

Various approaches may be used in various alternative embodiments inorder to communicate via the first frequency band associated with thefirst beamwidth (herein “first frequency band”) and the second frequencyband associated with the second beamwidth (herein “second frequencyband”). For example, in some embodiments, communication using the firstfrequency band may be as a result of using a relatively low frequencyband such as those bands less than about 20 GHz while communicationusing the second frequency band may be as a result of using a higherfrequency band such as those bands centered above about 20 GHz. Variousantenna systems that may include various combinations of antennas and/ormulti-element antennas may be employed in various alternativeembodiments in order to communicate using the first and the secondfrequency bands.

The first frequency band may be a lower frequency band than the secondfrequency band. For these embodiments, the first frequency band may bethe 2.4 GHz ISM band or the 5.0 GHz UNII band, or some other band lessthan about 20 GHz while the second frequency band may be a higherfrequency band such as a band greater than about 20 GHz, including forexample, the 24 GHz band or a band centered in the 59 to 62 GHz spectra.Note that for purposes of this description, the process of communicatingusing the first lower frequency band may be referred to as out-of-band(OOB) communications and the process of communicating using the secondhigher frequency band may be referred to as in-band communications. Notefurther that other frequency bands may also be used as the first andsecond frequency bands in alternative embodiments and that thedemarcation between the first lower frequency band and the second higherfrequency band may not be at 20 GHz. In still other alternativeembodiments, the first and the second frequency bands may be centered atthe same frequencies but may be associated with different beamwidths byusing, for example, antennas of different aperture sizes.

The first frequency band may be used by the communication device tocommunicate with the other communication devices of the wirelessnetwork, OOB control information signals or simply “first controlsignals” to facilitate data communication using the second frequencyband. The first control signals may comprise of “signals” and/or“control information” to facilitate initial or coarse beamforming, CFOestimation, timing synchronization, and so forth, of the device or theother communication devices. In some embodiments, the communicationdevice may use the second frequency band to transmit and/or receive toand/or from the other communication devices of the wireless network,in-band control information signals or simply “second control signals”to further facilitate data communication using the second frequencyband. The second control signals may be comprised of signals and controlinformation to facilitate fine beamforming, CFO estimation, timingsynchronization, and so forth, of the communication device or the othercommunication devices. The subsequent data or data signals to becommunicated (i.e., transmitted and/or received) using the secondfrequency band may include signals for tracking of the beamforming, CFO,timing, and so forth, as well as various types of data including, forexample, data relating to video streaming, realtime and/or non-realtimecollaboration, video content download, audio and text content downloadand/or upload, and so forth.

In order to appreciate various aspects of embodiments described herein,the characteristics of a frequency band associated with a relative broadbeamwidth and the characteristics of a frequency band associated with arelatively narrow beamwidth will now be discussed. This discussion willalso describe the characteristics of various types of antennasincluding, for example, omnidirectional and directional antennas. Inaddition, a discussion relating to the impact of using a lower asopposed to a higher frequency band will also be provided.

This discussion begins with a brief description of beamwidths. Abeamwidth is a spatial characteristic typically associated with antennasor dishes. The beamwidth of an antenna may be determined by the ratio ofthe antenna aperture size to the wavelength of the signals to betransmitted (or received). That is, the greater the aperture size, thenarrower the beamwidth if the wavelengths of the signals to betransmitted (or received) are held constant. Alternatively, thebeamwidth may also be made narrower by transmitting (or receiving)signals of shorter wavelengths (i.e., higher frequency) whilemaintaining a constant aperture size. Thus when an antenna or antennashaving similar sized apertures transmit signals of different frequencybands, different beamwidths may result. Note that although the abovediscussion relates to, among other things, the relationship betweenaperture size and beamwidth, multi-element antennas may be employed toselectively control the beamwidth of the signals to be transmitted, inwhich case aperture size may not be relevant as to beamwidth of thesignals to be transmitted. That is, antenna systems may be employed thathave multi-element antennas that may be adaptively configured toselectively transmit (or receive) signals associated with differentbeamwidths.

Thus, in order to obtain a relatively broad beamwidth, one approach isto use an antenna having a small aperture, such as an omnidirectionalantenna, instead of or in addition to using a relatively low frequencyband (e.g., ISM or UNII bands). In contrast, in order to obtain anarrower beamwidth, one approach is to use an antenna having a largeaperture, such as a directional antenna, instead of or in addition tousing a relatively high frequency band. Of course, alternatively, asingle antenna may provide varying beamwidths simply by varying thefrequency bands (i.e., either higher or lower frequency bands) of thesignals to be transmitted and/or received. In still other alternativeapproaches, and as previously alluded to, multi-element antennas may beemployed to provide frequency bands with varying beamwidths. That is, asingle set of multi-element antennas may be adaptively controlled using,for example, special procedures or protocols to provide specific beamdirections and specific beam shapes. Thus, a single set of multi-elementantennas may be employed to provide multiple frequency bands of varyingbeamwidths. Note that in the following description, the phrase “antenna”may refer to a single antenna or multi-element antennas.

Referring now to FIG. 2 comparing the beamwidths of various frequencybands using antennas with about the same aperture size. As previouslyalluded to, one of the properties of using a lower frequency band suchas the 2.4 GHz (ISM) band or the 5.0 GHz (UNII) band instead of a higherfrequency band such as an in-band frequency band (e.g., bands greaterthan 20 GHz) for communicating in a, for example, wireless network isthat the lower frequency bands may be associated with a greaterbeamwidth. Because of the greater beamwidth, signals transmitted via thelower frequency bands will likely reach more devices in the wirelessnetwork. However, because of the greater beamwidth, the drawback inusing a lower frequency band is that because of the broader wedge, thereis a greater risk of interference and interception.

In contrast to the lower frequency bands, when higher frequency bandsare used for communicating in a wireless network a narrower beamwidthmay result as previously described. As a result, there may be lesslikelihood of interference. In addition to the narrower beamwidth,another property of a higher frequency band is that if a higherfrequency band (such as the 24 or the 60 GHz band) is used then theremay be an additional attenuation with distance due to, for example,oxygen absorption. That is, and as depicted in FIG. 2, a higherfrequency band (e.g., 60 GHz band) may have a smaller beamwidth and ashorter “range” or “reach” than a lower frequency band (e.g., 2.4 or 5.0GHz bands). Thus, devices operating in the 60 GHz band instead of alower band such as the 2.4 or 5.0 GHz bands may typically have lessinterference risk from other remote devices.

Another characteristic of using a higher frequency band forcommunicating in a wireless network is that the higher frequency bandmay allow higher signal bandwidth to be used (as more spectra istypically available at higher frequencies) which may consequently allowgreater data throughput. At the same time, using the larger bandwidthmay decrease the power spectral density of the transmit signal andpotentially decrease the reliable communication range due to lesssignal-to-noise ratio at the receiver side.

The use of higher frequency bands for communicating in a wirelessnetwork may mean that a directional antenna rather than anomnidirectional antenna may be used for such communication. The use ofsuch an antenna by itself may offer certain advantages and disadvantageswhen used to communicate in a wireless network. For example, oneadvantage of using a directional antenna and the higher frequency bandfor transmitting signals is that less power may be needed in comparisonto using an omnidirectional antenna to achieve the same level ofreceived power. Thus, less efficient (and less expensive) radiofrequency (RF) components may be used with the directional antenna,which may be a significant factor in some situations as costs of RFparts may be significantly higher for higher frequency communication.

Of course, there may be certain drawbacks when communicating in awireless network using a higher frequency band with a directionalantenna. For example, adapted or multiple fixed antenna setting thatspans 360 degrees may be needed in order to register all of thecommunication devices in the network. This may be very time-consumingand synchronizing the communication device in the network using, forexample, protocols such as carrier sense multiple access and collisionavoidance (CSMA/CA) or carrier sense multiple access and collisiondetection (CSMA/CD) may be very difficult and may not be feasible when ahigher frequency band using a directional antenna is employed.

In accordance with various embodiments, the characteristics of frequencybands associated with different beamwidths as described above may becombined and used in a wireless communication network in accordance withvarious embodiments as described below.

FIG. 3 illustrates a wireless network that includes multiplecommunication devices (CDs) that are in communication with each othervia multiple communication links in accordance with various embodiments.For the embodiments, the network 300 may be WWAN, WMAN, WLAN, WPAN, orother types of wireless networks. The communication devices (CDs)302-308 may be desktop computers, laptop computers, set-top boxes,personal digital assistants (PDAs), web tablets, pagers, textmessengers, game devices, smart appliances, wireless mobile phones orany other types of computing or communication devices. In someembodiments, at least one of the CDs 302-308 may be a master or anaccess point, while the other CDs may be the client or slave devices.Note that in alternative embodiments, the network 300 may include moreor fewer CDs. Each of the CDs 302-308 may communicate with the other CDsof the network 300 via links 310 that may be bidirectional.Communication between the CDs may be in accordance with standards suchas 802.11a, 802.11b, and other derivatives of these standards.

For ease of understanding, embodiments of the present disclosure will befurther described assuming that the network 300 is a WPAN and that CD302 is the access point and that the other CDs 304-308 are the clientdevices. Note that in alternative embodiments, the network 300 may notinclude an access point. For example, the network 300 may be an ad-hocmesh network in alternative embodiments, in which case, the access pointis not needed. Returning to FIG. 3, in some embodiments, at least someof the client CDs 304-308 may arbitrarily and randomly join and/or leavethe network 300. Each time a client CD 304-308 enters the network 300,it may authenticate or associate (herein “associate”) with the network300 so that the various client CDs of the network 300 may “know” thatthe client CD is present in the network 300. In some embodiments, aclient CD 304-308 may associate with the network 300 by associating withthe access point CD 302. Note that in this illustration, client CD 304has just entered the network 300 as indicated by reference 312.

The CD 304 upon entering the network 300 may associate itself with thenetwork (e.g., via access point CD 302). In accordance with variousembodiments, association with the network 300 may be accomplished using,for example, a first frequency band associated with a relatively broadbeamwidth. By transmitting the association signals using a frequencyband associated with a relatively broad beamwidth (herein “firstbeamwidth”), the other CDs 302, 306, and 308 in the network 300 may bemore likely to receive the authentication signals (e.g., beacons) fromCD 304. In some embodiments, the first frequency band may be a 2.4 GHz(ISM), a 5.0 GHz (UNII), or other bands that may be less than, forexample, 20 GHz. Note that the access point CD 302 may listen for (i.e.,authentication or association) an entering CD 304 through signalstransmitted in the first frequency band. After successfully registeringor associating with the network 300 (which may be effectuated via anyone of a number of association and/or authentication protocols), thecomponents of CD 304 may then “sleep” until it receives datatransmission from one of the other CDs in the network or is ready totransmit data to the network 300 (i.e., to one or more of the other CDsin the network 300).

When the client CD 304 is ready to transmit signals to one or more ofthe other CDs 302, 306, and 308 in the network 300 (including the accesspoint CD 302), it may initially transmit first control signals thatinclude control information using again the first frequency bandassociated with the first beamwidth. In using the first frequency bandassociated with the first beamwidth, the other CDs 302, 306, and 308 inthe network 300 are more likely to “hear” or receive the signalstransmitted by the client CD 304. This may provide the opportunity toreduce the interference in the second frequency band because the devicesare now aware of intentions of the CD 304 and may therefore defer theirtransmission for the appropriate time period. In various embodiments,the other CDs 302, 306, and 308 may determine the signal parameters ofthe first control signals transmitted by the client CD 304. By measuringthe signal parameters, the other CDs 302, 306, and 308 may determine thesignal strength and the angle of arrival of the first control signals.As a result, the other CDs 302, 306, and 308 may be facilitated indetermining the distance between the other CDs 302, 306, and 308, andthe client CD 304.

Further, the location, at least in part of CD 304 relative to the otherCDs (e.g., in terms of azimuth and elevation) may be determined by theother CDs 302, 306, and 308 based at least in part on the angle ofarrival of the initial signals using the first frequency band. Thesedeterminations, in effect, may facilitate further communication using asecond frequency band associated with a relatively narrow beamwidth.That is, the antenna systems employed by the other CDs 302, 306, and 308may be properly configured and/or aligned based on the determinations tofacilitate further communication using the second frequency band betweenthe CDs 302, 306, and 308, and the client CD 304.

The first control signals transmitted through the first frequency bandmay facilitate initial communication between the CD 304 and the otherCDs 302, 306, and 308 of the network 300; including signals and/orcontrol information for coarse configuration by the other CDs 302, 306,and 308 to communicate with CD 304. The devices subsequently communicateusing a second frequency band that is associated with a second beamwidththat may be a narrower beamwidth than the first beamwidth of the firstfrequency band. In some embodiments, the first control signals mayinclude signals for medium access control (MAC) mechanism data such asdata associated with CSMA/CA or CSMA/CD. Again, by using the firstfrequency band associated with the relatively broad beamwidth forcommunicating data, such as MAC mechanism data, each of the other CDs302, 306, and 308 are more likely to receive the MAC mechanism data. Thefirst control signals may further include signals as well as controlinformation for initial beam forming parameters such as beam formingcoefficients, synchronization parameters, initial CFO estimation,detection, and so forth. In particular, in some embodiments, the firstcontrol signals may be adapted to facilitate beam forming, CFOestimation, and/or synchronization of the other CDs 302, 306, and 308.

In some embodiments, where one or more of the CDs 302-304 employ antennasystems that include multi-element antennas, the first control signalstransmitted using the first frequency band may include signals thatfacilitate different diversity techniques (e.g., antenna selection andmaximum ratio combining), space-time codes (e.g., Alamouti code), andMIMO techniques.

The second frequency band may be a higher frequency band than the firstfrequency band. For example, the second frequency band may be an in-bandband (i.e., greater than 20 GHz) such as the 24 GHz band or a frequencyband in the 59-62 GHz spectra. The higher frequency bands, such as thosegreater than 20 GHz, may provide greater bandwidth than lower frequencybands (e.g., 2.4 GHz and 5.0 GHz). In various embodiments, communicationusing the second frequency band may be in accordance with a particulartechnique such as OFDM or other modulation techniques. Note that in somealternative embodiments, the first and the second frequency bands may besubstantially the same frequency bands but may be associated withdifferent beamwidth by using, for example, antennas of differentaperture sizes or using an antenna system that employs multi-elementantennas. Further note that if CD 304 is unable to communicate using thesecond frequency band, then CD 304 may operate in a fall-back operationmode in which communication is entirely via first frequency band atleast until the second frequency band is made available. Such afall-back mode may be needed, for instance, if the transmitting andreceiving devices cannot “see” each other using the second frequencyband.

After the first control signal has been transmitted using the firstfrequency band to facilitate communication, second control signals maybe transmitted using the second frequency band to further establishcommunication. The second control signals may include signals and/orcontrol information to facilitate fine beam forming, fine CFOestimation, synchronization, and so forth, by the other CDs 302, 306,and 308. Once further communication using the second frequency band hasbeen established, signals for tracking of beam forming, CFO, timing, andso forth, as well as signals that include data such as video streaming,real-time collaboration, video content download, and the like may becommunicated using the second frequency band.

When client CD 304 is to leave the network 300 as indicated by reference314, the client CD 304 may exchange various exit information orparameters with the network 300 (e.g., access point CD 302) prior toexiting the network 300. Upon exiting the network 300, CD 304 maytransmit exit information through the first frequency band. The exitinformation may include the reason code such as bad signal quality, orjust does not want to communicate any more (the application has closed),or was not authorized to enter the network, and so forth.

FIG. 4 illustrates some types of CSMA/CA data that may be communicatedvia a first and a second frequency band in a wireless network inaccordance with various embodiments. In particular, FIG. 4 shows threenodes A, B, and C communicating with each other in accordance with theCSMA/CA protocol. The first frequency band is associated with a firstbeamwidth and the second frequency band is associated with a secondbeamwidth, and the first beamwidth is wider or larger than the secondbeamwidth. For the embodiments, the Distributed Coordination Function(DCF) Inter Frame Space (DIFS), the Short Inter Frame Space (SIFS), andthe Contention Window (CW) may be facilitated using the first and thesecond frequency band, while the MAC Protocol Data Unit (MPDU) and theAcknowledge (Ack) may be communicated using the first and/or the secondfrequency bands.

FIG. 5 illustrates a process for communication between devices of awireless network using a first and a second frequency band, where thefirst frequency band has a first beamwidth that is broader than a secondbeamwidth associated with the second frequency band. The process 500 maybe practiced by various communication devices and may begin with acommunication device entering the network at 504. After entering thenetwork, the communication device may use a first frequency band (e.g.,2.4 GHz ISM band or 5.0 GHz UNII band) associated with a first beamwidthto register with the network at 506. If the communication device hasfinished communicating (e.g., transmitting and/or receiving) at 508 thenthat device may exchange exit information with the network and proceedto exit the network at 510.

On the other hand, if the communication device is not yet finishedcommunicating with the network (i.e., one or more communication devicesof the network) at 508, then the communication device may exchangecontrol signals with other devices using the first frequency band, andthen communicate with the other devices using a second frequency bandassociated with a second beamwidth at 512. Note that the term “exchange”as used herein may be a bidirectional or a unidirectional exchange ofsignals. The second frequency band may then be used to communicatesecond control signals having signals and/or control information thatfacilitate further communication using the second frequency band at 514.The second control signals may include, for example, signals and/orcontrol information for fine beam forming, fine CFO estimation, and/orsynchronization, that may supplement the first control signals that wereexchanged using the first frequency band in order to further establishcommunication using the second frequency band. Once communication hasbeen further established using the second frequency band, signalscarrying various data may be exchanged at 516. After the communicationdevice has finished communicating with the devices of the network usingthe second frequency band, the process 500 may repeat itself byreturning to 508.

FIG. 6 depicts portions of a communication device (CD) 600 that includesa protocol stack 604 having a number of layers including an applicationlayer 606, a network layer 608, a medium access control (MAC) layer 610,and a physical (PHY) layer 612. The CD 600 may further include acontroller 602 such as a processor or microcontroller to coordinate theactivities of various components associated with the various layers ofthe CD 600. The components of PHY layer 612 may be coupled to twoantennae 614 and 616. In some embodiments, one antenna 614 may be anomnidirectional antenna while the other antenna 616 may be a directionalantenna. For these embodiments, the omnidirectional antenna may beadapted to transmit and/or receive signals of a first frequency bandassociated with a first beamwidth while the directional antenna may beadapted to transmit and/or receive signals of a second frequency bandassociated with a second beamwidth. Again, the first beamwidth may begreater than the second beamwidth. In some embodiments, the firstfrequency band may be a lower frequency band than the second frequencyband. In alternative embodiments, only a single antenna may be coupledto the PHY layer 612. In still other alternative embodiments, the PHYlayer 612 may include or may be coupled to an antenna system that mayemploy, for example, one or more multi-element antennas to transmitand/or receive signals using the first and the second frequency bandsassociated with the first and the second beamwidths, respectively.

Various embodiments described herein may be practiced by the componentsof the MAC and PHY layers 610 and 612 of the CD 600 (hereinafter, simplyMAC and PHY layers). PHY layer 612 may be adapted to transmit and/orreceive first signals (i.e., first control signals) using a firstfrequency band to facilitate establishment of initial communicationusing a second frequency band. The PHY layer 612 may be further adaptedto transmit and/or receive second signals (i.e., second control signals)using the second frequency band to facilitate further communicationusing the second frequency band to communicate third signals carryingdata. The MAC layer 610, in contrast, may be adapted to select the firstor the second frequency bands to be used by the PHY layer 612 totransmit and/or receive the first, the second and/or the third signals.

The omnidirectional antenna 614 may be used to transmit and/or receivethe first signals via the first frequency band to facilitate initialcommunication between the CD 600 and other CDs of a wireless networkusing the second frequency band. In contrast, the directional antenna616 may be used to transmit and/or receive the second and third signalsusing the second frequency band, the communication using the directionalantenna 616 at least in part being initially established via the firstsignal transmitted and/or received using the omnidirectional antenna614. In order to practice the various functions described above for CD600 as well as the functions described previously, the CD 600 mayinclude a physical storage medium adapted to store instructions thatenables the CD 600 to perform the previously described functions.

FIG. 7 illustrates a circuitry for transmitting and/or receiving signalsusing a first and a second frequency band in accordance with variousembodiments. The circuitry 700 may operate in a wireless networkenvironment and may include, among other things, transmitter circuitry702, receiver circuitry 704, frequency synthesizer 706, and antennae708-714. Note that in alternative embodiments, the circuitry 700 mayemploy any number of antennas. Note further that the term “antennae” and“antennas” as used herein are synonymous.

In various embodiments, the circuitry 700 may operate in an OrthogonalFrequency Multiple Access (OFMA) environment. The circuitry 700 mayinclude zero intermediate frequency (ZIF) circuitry, super heterodynecircuitry, direct conversion circuitry, or other types of circuitry. Insome embodiments, the circuitry 700 may be one of the circuitries asdisclosed in U.S. patent application Ser. No. 11/394,600, entitled“Systems For Communicating Using Multiple Frequency Bands In A WirelessNetwork.”

The frequency synthesizer 706, in some embodiments, may be a frequencysynthesizer that provides both a first lower modulation frequency signal716 and a second higher modulation frequency signal 718, such as a2.4/60 GHz frequency synthesizer, to the transmitter and receivercircuitries 702 and 704. The first and the second modulation frequencysignals 716 and 718 may be used to modulate and/or demodulate signals tobe transmitted or received using the first and the second frequencybands, respectively. The transmitter circuitry 702 may be coupled to afirst antenna 708 that may be an omnidirectional antenna, and a secondantenna 710 that may be a directional antenna. The receiver circuitry704 may be coupled to a third antenna 712 that may be a directionalantenna, and a fourth antenna 714 that may be an omnidirectionalantenna.

In various embodiments, the relative CFO for circuitry 700 may bedefined by the reference oscillator stability. Thus the same oscillatormay be employed for both the OOB (e.g., first frequency band) and thein-band band (e.g., second frequency band) operations. Accordingly, theabsolute value of the CFO may be much higher for the in-band (secondfrequency band) operations.

The initial CFO estimation and compensation problem for such a system issolved using the OOB operations. For example, the frequency synthesizer706 is designed in such a way that both the in-band frequency synthesiscircuitry and OOB frequency synthesis circuitry use the same referenceclock oscillator. In this case, the signals transmitted at both OOBfrequency and in-band frequency may have the same relative (in ppm)CFOs. An initial estimation of the CFO at the receiving end may be donefor the OOB signal, and after that, an estimate may be recalculated andused for the coarse frequency offset compensation at the in-bandfrequency. The entire system may also use OOB signaling for tracking of,for example, timing, carrier frequency offset and so forth.

FIG. 8 illustrates a frame format for communicating in a wirelessnetwork using a first and a second frequency band in accordance withvarious embodiments. Frame format 800 may represent the format of thesignals to be transmitted and/or received by a communication device toand/or from another communication device of a wireless network. Thefirst frequency band (i.e., out-of-band (OOB) frequency band) may be alower frequency band such as a frequency band less than about 20 GHzwhile the second frequency band (i.e., in-band frequency band) may be afrequency band above about 20 GHz. Further note that because of thegreater spectra available in the higher frequency bands, the secondhigher frequency band may have a bandwidth of about 1-2 GHz or morewhile the first lower frequency band may only have a bandwidth ofseveral MHz.

The frame format 800 includes an OOB preamble 802 to be communicated viathe first frequency band that may be embodied in signals adapted forsignal detection, initial carrier frequency offset (CFO) estimation,and/or initial beam forming. Note that the term “preamble” as usedherein is to be broadly interpreted and may mean any type of data packetor portion of a data packet. In some embodiments, the OOB preamble mayinclude medium access control data such as data relating to CSMA/CA orCSMA/CD data.

The frame format 800 may further include an in-band preamble 804 andin-band data 806 to be communicated using the second frequency band. Thein-band preamble 804 may be embodied in signals that are adapted forfiner timing synchronization, finer CFO estimation, and/or finer beamforming. The signals for the in-band preamble 804 may supplement thecontrol signals (e.g., initial CFO estimation, initial beam forming, andso forth) exchanged using the first frequency band. As a result, thein-band preamble 804 may further facilitate communication using thesecond frequency band in order to facilitate communication of thein-band data 806. Special field symbols may be placed after the OOBpreamble 802 to provide encoded service information that may be neededfor consequent data symbols and in-band packet decoding (e.g.,modulation and coding scheme used, and so forth).

In order to appreciate certain aspects of the signals that embody theframe format 800, a more detailed explanation of CFO will now beprovided. CFO is the difference between the carrier frequencies that thetransmitter and the receiver are tuned at. Although CFO estimation maybe more accurately determined when it is determined using the preamble(i.e., preamble signals) of a higher frequency band such as the in-bandpreamble 804, an initial CFO estimation may be initially determinedusing the OOB preamble 802 (i.e., OOB preamble signals) to partiallydetermine the CFO prior to fine estimation of the CFO using the in-bandpreamble 804. As a result, by including signals for initial CFOestimation in the signals embodying the OOB preamble 802, the task offine CFO estimation may be simplified.

The in-band preamble 804 (i.e., in-band preamble signals) may be adaptedfor fine CFO estimation, which may supplement the initial CFO estimationperformed using the OOB preamble 802. The CFO is the frequencydifference between the reference clock oscillator in the transmittingdevice and the reference clock oscillator in the receiving device. Sincethe reference oscillators determine the “time scales” of thetransmitting device and the receiving device, the CFO may be determinedby the product of the difference of the reference oscillator frequenciesexpressed in percent with respect to the absolute value of thosefrequencies, and the value of carrier frequency expressed in Hertz. CFOestimating schemes are typically more sensitive to the absolute value ofthe difference between the carrier frequencies of the receiver and thetransmitter, noting that the greater the carrier frequency, the higherthe achievable CFO values. Thus, improved accuracy may be obtained forCFO estimates when they are determined using preamble signals that arecommunicated using a higher frequency band such as an in-band frequencyband.

The signals embodying the OOB preamble 802 may be adapted for initialbeam forming. As used herein, initial beam forming refers to an initialprocess in beam forming calculations that may include preliminaryestimation of angle of arrival of a signal wave front from a remotetransmitting device. This operation may facilitate preliminaryadjustments of the antenna system of the receiving device in order forthe receiving device to receive the subsequent in-band preamble. Thisoperation may also reduce the search interval for angle of arrival ofthe in-band signals. For example, initial beam forming may point to asector where the remote transmitting device is operating. If the antennaof the receiving device has multiple substantially narrow sectors, thenthe initial beam forming may reduce the number of sectors to search forthe subsequent in-band signals.

In order to supplement the initial beam forming, signals embodying thein-band preamble 804 may be adapted for fine beam forming. Fine beamforming may refer to the process of fine or precise antenna adjustmentto improve the receiving quality of, for example, in-band signals (i.e.,signals transmitted through second frequency band). Depending on thebeam forming algorithm used, this may include choosing the optimalantenna or optimal sector within the antenna where the signal qualitymetrics are the best. Fine beam forming may also include calculations ofcomplex coefficients (or only phase shift values) for combining thesignals coming from different antennae or from different sectors withinthe sectored antenna.

The signals embodying the OOB preamble 802 may be adapted for signaldetection. That is, the signals containing the OOB preamble 802 may beadapted to facilitate signal detection and to indicate to the receivingdevices that the signals are “valid” signal. The signals containing theOOB preamble may be adapted to indicate to the receiving device ordevices that it is a signal containing a “valid” message from a networkcommunication device rather than just noise or interference. Currently,the Federal Communications Commission (FCC) allows greater powerspectral density in the lower bands (e.g., 2.4 GHz and 5.0 GHz bands),and therefore, signal detection may be more easily performed in theselower bands because of the higher probability that “valid” signals willbe properly detected when the lower bands are used.

The signals embodying the in-band preamble 804 may be adapted for finetiming synchronization. Fine timing synchronization may relate to aprocess that finds boundaries of informational symbols within a receivedsignal. Since the signals of the in-band preamble 804 have greaterspectrum bandwidth (relative to the OOB preamble signals), these signalsmay be designed to have, for example, better correlation properties thanthe signals embodying the OOB preamble 802. Therefore, by including finetiming synchronization signals with the signals embodying the in-bandpreamble 804, more precise timing estimation and therefore bettersynchronization may be obtained.

Once communication using the second frequency band has been fullyestablished as a result of communicating the OOB preamble 802 and thein-band preamble 804, in-band data 806 may be communicated via thesecond frequency band as shown in FIG. 8. The in-band data 806 mayinclude for example, video streaming, real-time collaboration, videocontent download, and so forth.

FIG. 9 depicts frame format 900 that includes OOB preamble 802, in-bandpreamble 804, and in-band data 806, similar to the frame format 800 ofFIG. 8, as shown. However, unlike the frame format 800 of FIG. 8, theframe format 900 includes a time gap 902. The time gap 902 separates theOOB preamble 802 and the higher-frequency part of the frame (e.g.,in-band preamble 804) to allow the receiver circuitry of the receivingdevice to switch between the first and second frequency bands and toallow the subsequent relaxation processes in the circuitries, such asfilters, to finish (see, for example, FIG. 7).

FIG. 10 depicts still another frame format for communicating in awireless network using a first and a second frequency band in accordancewith various embodiments. The frame format 950 is similar to the frameformat 900 of FIG. 9 except that the first frequency band may be used,after the time gap 902, for tracking and/or sending service informationas indicated by reference 952. That is, the first frequency band may beused for tracking of beamforming, CFO, timing, and so forth, and/or forsending service information such as channel access signals. Note that inalternative embodiments, the time gap 902 may not be present. Furthernote that the OOB part of the frame format 950 may contain signals suchas pilot or training signals.

The previous embodiments refer to “hard” coupled systems thatcommunicate using a first and a second frequency band, whereincommunication using the second frequency band is a result of thecommunication using the first frequency band. In other words, the hardcoupled systems use the first frequency band to communicate signals(e.g., first control signals) to facilitate subsequent communicationusing the second frequency band.

In alternative embodiments, however, “soft” coupled systems arecontemplated that may use two frequency bands independently so thatsignal transmission or reception using a first frequency band mayoverlap the signal transmission or reception by the same system using asecond frequency band. For these embodiments, the first frequency bandmay be a lower frequency band such as those below 20 GHz (e.g., 2.4 GHzor 5.0 GHz bands) and the second frequency band may be a higherfrequency band such as those above 20 GHz (e.g., in-band bands).

The soft coupled system may use the first lower frequency band forprocedures that may not require a high data throughput rate such asnetwork entry, bandwidth requests, bandwidth grants, scheduling thetransmissions in a second higher frequency band, transferring feedbackinformation that may comprise beam forming information and power controlinformation, and so forth. In contrast, the second higher frequency bandmay be used for data transmission at relatively high data throughputrates.

FIG. 11 depicts frame formats for both a first and a second frequencyband for a soft coupled system. The first frame format 1102 isassociated with a first frequency band 1100 while the second frameformat 1104 is associated with a second frequency band 1101. The firstfrequency band 1100 may be a frequency band below 20 GHz while thesecond frequency band 1101 may be a frequency band above 20 GHz. Theframe formats 1102 and 1104 may include respective preambles 1110 and1116, frame PHY headers 1112 and 1118, and frame payloads 1114 and 1120.Each of the preambles 1110 and 1116 may be adapted for frame detection,timing and frequency synchronization, and so forth, similar to that ofthe hard coupled system previously described. However, unlike the hardcoupled system, the preambles 1110 and 1116 of these frame formats 1102and 1104 may be processed independently with respect to each other. Thepreambles of both frame formats 1102 and 1104 may be embodied in signalsadapted for coarse and fine estimations of CFO, timing synchronization,beam forming, and so forth.

Both of the frame formats 1102 and 1104 may include PHY headers 1112 and1118 to indicate at least the amount of data carried in their associatedframe payloads 1114 and 1120. The PHY headers 1112 and 1118 may alsoindicate the modulation and/or coding type to be applied to the framepayloads 1114 and 1120, beam forming control information, power controlinformation of the payload, and/or other parameters. The frame PHYheaders 1112 and 1118 may be modulated and coded using, for example, apredetermined modulation and coding type, a predetermined beam forming,and a predetermined power control that may be applied to the PHY headers1112 and 1118.

Both frame formats 1102 and 1104 may include a frame payload 1114 and1120 to carry payload data. The frame payloads 1114 and 1120 of bothframe formats 1102 and 1104 may include additional sub-headers tocontrol the interpretation of the information within the payload, suchas MAC layer headers that may indicate, for example, the source and/ordestination addresses of the frame.

The frame payload 1114 of the first frame format 1102 may containchannel access control information such as bandwidth requests andgrants. It may also contain special messages used for network entry, andtest signals for measurement of distance between stations in thenetwork, although these functionalities may be carried by the preamble1110 in alternative embodiments. The first frame format 1102 may furtherinclude fields for sending feedback information from the destination ofthe packet back to its source, the feedback information relating to, forexample, power control, rate control, beam forming control, for sendingchannel state information, receiver and/or transmitter performanceindicators such as bit error ratio, current transmit power level, and soforth.

The frame payload 1120 of the second frame format 1104 may includeinformation relating to higher network protocol layers.

The PHY headers 1112 and 1118 and/or the frame payloads 1114 and 1120 ofboth the first and the second frame formats 1102 and 1104 may includepilot signals for estimation and/or tracking of channel transferfunctions, maintaining timing and/or frequency synchronization, andother service tasks.

Accessing of a wireless channel of a wireless network using the firstfrequency band 1100 may be based on contention between communicationdevices (e.g., stations) of the wireless network. Different techniquesmay be applied to resolve the collisions that may be possible due tocontention. These techniques may include, for example, CSMA/CA, CSMA/CD,and so forth. Different division techniques may be used to reduce thenumber of collisions and include, for example, code division andfrequency or time division of contention opportunities, and so forth.Accessing of the wireless channel using the first frequency band 1100may include deterministic mechanisms provided that contention-basedaccess takes place. Frame exchange sequences in the first frequency band1100 may include special beacon frames transmitted periodically tofacilitate the frame exchange in the first frequency band 1100. Thetransmission of frames in the first frequency band 1100 other thanbeacons may occur in substantially random moments of time.

In contrast to the above approaches for accessing a wireless channelusing the first frequency band 1100, accessing of a wireless channelusing the second frequency band 1101 may be deterministic and may bebased on a schedule that may be derived as a result of communicationsusing a lower frequency band (e.g., first frequency band 1100). This mayallow for more effective use of the high-throughput channel in thehigher second frequency band 1101 as a result of reducing the timeoverhead for channel access by reducing the overhead of the backing-offand retransmissions caused by collisions taking place when using, forexample, random channel access methods.

The first frequency band 1100 may be a lower frequency band while thesecond frequency band 1101 may be a higher frequency band. The firstfrequency band 1100 may be associated with a first bandwidth 1106 whilethe second frequency band 1101 may be associated with a second bandwidth1108, the second bandwidth 1108 being greater than the first bandwidth1106. Selected types of payloads may be communicated via the firstfrequency band 1100 while other types of payloads may be communicatedusing the second frequency band 1101. For example, network controlmessages are typically short and comprised of few tens of bytes of data,while higher layer payload information may contain several thousandbytes or more. Therefore, network control messages may be communicatedusing the first frequency band 1100 while the second frequency band 1101may be used in order to communicate the higher layer payloadinformation.

FIG. 12 illustrates a transmitter/receiver circuitry of a soft coupledsystem for independent dual-band communication. The circuitry 1200 maybe comprised of a transmitter circuitry 1202 and a receiver circuitry1204. The circuitry 1200 may be coupled to a MAC layer that may controlvarious functionalities and may include, among other things, a frequencysynthesizer 1206, a 90 degree phase splitter 1208, antennae 1210 and1212, and switches 1214 and 1216. The frequency synthesizer 1206 may bea 2.4/5.0/60 GHz frequency synthesizer. As depicted, the transmitter andreceiver circuitry 1202 and 1204 are coupled to the two antennae 1210and 1212 via switches 1214 and 1216. In alternative embodiments,however, the transmitter and receiver circuitry 1202 and 1204 may becoupled to any number of antennas. In some embodiments, the firstantenna 1210 and the second antenna 1212 may be adapted to transmitand/or receive a first and a second frequency band, respectively,wherein the first frequency band being a lower frequency band (e.g.,UNII/ISM frequency bands) than the second frequency band (e.g., in-bandbands). In various embodiments, switches 1214 and 1216 may be coupled toand controlled by the MAC layer to selectively communicate using, forexample, an UNII/ISM frequency band and/or an in-band band.

FIG. 13 illustrates another process 1300 for communicating by acommunication device in a wireless network in accordance with variousembodiments. The process 1300 may be a transmission procedure for acommunication device to communicate with a neighboring communicationdevice and/or a coordinating device using a lower frequency band (“lowerband”) such as the first frequency band and a higher frequency band(“higher band”) such as the second frequency band. For example, theprocess 1300 may be suitable for embodiments described in connectionwith at least FIGS. 8-10 where communication in the higher band ispreceded with communication in the lower band. Communication devices ofa wireless network may be referred to as “nodes” herein. A coordinatingdevice is described further in connection with at least FIG. 19.

At block 1302, the process 1300 includes listening, by a communicationdevice, to the air in the higher and lower bands to determine, at block1304, whether another communication device and/or a coordinating devicetransmits in the higher or lower band. The communication device maylisten to the air, for example, by detecting energy at a receiverantenna in the lower and/or higher band. A determination as to whetheranother communication device and/or a coordinating device transmits inthe higher or lower band may be based, for example, on energy detectedat the receiver antenna or on information decoded from headers (e.g.1118) and/or frame contents (e.g., 1112).

If the communication device determines that another device istransmitting, then the communication device may receive, at block 1306,signals and/or control information in the higher and/or lower bands todetermine how long a medium of the other device will be busy. Thereceived signals and/or control information may include, for example, apreamble comprising medium access control data including data forcarrier sense multiple access and collision avoidance (CSMA/CA) orcarrier sense multiple access and collision detection (CSMA/CD). Thepreamble may be a physical layer signal and may include a lower-bandframe that includes information about a channel reservation for a higherband as part of a dual-band frame. Receiving lower band communicationmay allow early detection of transmission in the higher band. If thecommunication device fails to receive communication in the lower band,the communication device may be able to detect energy at the higherband.

If the communication device determines, at block 1304, that othercommunication/coordinating devices are not transmitting in the higher orlower band then the communication device may use a transmission protocolthat initiates transmission in the lower band, at block 1308, followedby subsequent transmission in the higher band, at block 1310. Thecommunication device may continue transmitting in the lower band whentransmitting in the higher band, at block 1310.

FIG. 14 illustrates yet another process 1400 for communicating by acommunication device in a wireless network in accordance with variousembodiments. The process 1400 may be suitable for a case wherecommunication in the higher band is arranged in the lower band andsynchronized at the physical layer with signals in the lower band (e.g.as described in connection with FIG. 10).

Because both the upper band and lower band are synchronized, listeningto the air, at block 1402, may be performed using only the lower band.If the communication device determines that anothercommunication/coordinating device is transmitting in the lower band, atblock 1404, then the communication device may receive signals, at block1406, and/or control information in the lower and/or higher bands todetermine how long a medium of the transmitting device will be busy.

In an embodiment, signals and/or control information such as, e.g.,headers and/or information associated with a transmission schedule, isreceived by the communication device, at block 1406, in the lower band.The communication device may use the lower band only in such embodimentto determine eligible time slots to start transmission in the lowerband, at block 1408. In an embodiment where signals and/or controlinformation are received by the communication device, at block 1406, inthe higher band, the communication device may decode the signals and/orcontrol information from the higher band. A communication device orsystem may be designed to implement one or both, or combinations, ofsuch embodiments.

If other communication devices are not transmitting in the lower band,at block 1404, then the communication device may start transmission inthe lower band, at block 1408. The communication device may subsequentlystart transmission in the higher band and may continue transmitting inthe lower band, at block 1410. In an embodiment, the communicationdevice transmits in the lower band, at block 1408, and in the higherband, at block 1410, according to embodiments described in connectionwith actions 512, 514, and 516 of FIG. 5.

FIG. 15 illustrates a search procedure 1500 by a communication device ina wireless network in accordance with various embodiments. The searchprocedure 1500 may depict operations performed by a communication devicethat is not aware of the presence of another communication/coordinatingdevice (e.g. upon powering on the communication device).

At block 1502, the communication device may listen to the air in thelower band to determine, at block 1504, whether othercommunication/coordinating devices are transmitting in the lower band.For example, the communication device may determine whether a signalfrom another communication device is received in the lower band. If asignal from a neighboring communication device is received, thecommunication device may communicate with the neighboring communicationdevice using the lower band, at block 1506, to determine the higher bandcapability of the neighboring communication device. If the neighboringdevice is capable of communicating in the higher band, the communicationdevice may start a procedure of antenna adjustment in the higher band asdescribed in connections with FIGS. 16 and 17.

However, if a signal is not received by the communication device atblock 1504, e.g., within a pre-determined amount of time, then thecommunication device may continue listening to the air at block 1504.Alternatively, the communication device may transmit a beacon signal inthe lower band, at block 1510, so that other communication devices maydetect the presence of the communication device.

FIG. 16 illustrates an antenna adjustment/link establishment procedure1600 by a communication device in a wireless network in accordance withvarious embodiments. The antenna adjustment/link establishment procedure1600 may be initiated, for example, by one of the communication deviceor a neighboring communication/coordinating device that indicates acapability to communicate using the higher band (hereinafter“initiatior”).

At block 1602, the initiator may transmit a test signal in the higherband to an intended recipient (hereinafter “target receiver”) such asanother communication and/or coordinating device. The test signal may betransmitted to facilitate measurements and/or adjustments by the targetreceiver to establish a communication link in the higher band.

If the target receiver receives the test signal at block 1604, then alink is established in the higher band at block 1606. The initiator maynotify the target receiver (e.g., peer station) and/or a coordinatingdevice that the link in the higher band is established.

If the target receiver does not receive the test signal at block 1604,then the initiator and/or the target receiver may adjust or re-adjustrespective transmitters and receivers (e.g., directional antennas) atblock 1608 to allow transmission of another test signal in the higherband. In an embodiment, operations at block 1602, 1604, and 1608 arerepeated until the initiator and/or the target receiver have tested allpositions or combinations of positions of the antennas (e.g.,directional antennas). For example, if the initiator and the target nodehave not tested all positions or combinations of positions, at block1610, then operations 1602, 1604, and 1608 may be repeated until thelink is established, at block 1606. If the initiator and the target nodehave tested all positions and/or combinations of positions of theirrespective antenna, then they may fail to establish a link in the higherband, at block 1612. Such failure to establish a link may be reported toa coordinating device.

FIG. 17 illustrates another antenna adjustment/link establishmentprocedure 1700 by a communication device in a wireless network inaccordance with various embodiments. At block 1702, the procedure 1700starts with testing all possible combinations of antenna orientations atthe initiator and the target node. For example, the initiator mayrepeatedly transmit a test signal followed by re-positioning ofdirectional transmitters/receivers of the initiator and the target nodeuntil all combinations of antenna orientations have been tested.

If any of the tested orientations results in a received test signal bythe target node hosting the target receiver, at block 1704, then a linkis established in the higher band at block 1706. The initiator maynotify the target receiver (e.g., peer station) and/or a coordinatingdevice that the link in the higher band is established. Otherwise, ifnone of the tested orientations result in a received test signal by thetarget node, at block 1704, then the initiator and the target node failto establish a link in the higher band, at block 1708. Such failure toestablish a link may be reported to a coordinating device.

FIG. 18 illustrates a signal reception procedure 1800 by a communicationdevice in a wireless network in accordance with various embodiments. Theprocedure 1800 may be suitable for signal reception by a communicationdevice having synchronized signals for the upper band and lower band(e.g., using a common reference oscillator) as described in connectionwith FIGS. 8-10.

At block 1802, a communication device detects test signals transmittedin the lower band and performs, at block 1804, coarse estimation and/oradjustment of timing and frequency offsets using the test signalsdetected in the lower band. At block 1806, the communication deviceperforms a fine estimation and/or adjustment of the timing and frequencyoffsets using test signals transmitted using the higher band. At block1808, the communication device receives a data payload using the higherband.

FIG. 19 illustrates a communication system 1900 using a coordinatingdevice 1902 in accordance with various embodiments. One or morecommunication devices (e.g., 1904, 1906, 1908, 1910) may be capable ofcommunicating in a higher band and in a lower band using, for example,transceivers (e.g., TX/RX 0, TX/RX 1, TX/RX 2, TX/RX 3) according toembodiments described herein. Higher band communication (e.g. links1920, 1922, 1924, 1926, 1928) may be performed, for example, usingdirectional antennas that may be mechanically and/or electronicallysteered. Lower band communication (e.g., 1912, 1914, 1916, 1918) may beperformed, for example, using antennas that are substantiallyomni-directional.

Lower band communication (e.g., 1912, 1914, 1916, 1918) may be used tomanage access to a channel in the upper band. For example, acoordinating device 1902 may use the lower band to assign time and/orfrequency resources (e.g., a time interval) for one or more of thecommunication devices (e.g., 1904, 1906, 1908, 1910) to determinewhether neighboring communication devices have capability, availability,and/or sufficient link quality in the higher band to establishcommunication using the higher band. Using the assigned time/and orfrequency resource, the one or more communication devices may, forexample, determine link availability of the higher band by performinglink establishment procedures such as search routines using the higherband, and report the link availability to the coordinating device 1902using the lower band. The coordinating device 1902 can collect linkavailability from the one or more communication devices to create aconnectivity table or schedule for communication devices that cancommunicate with each other using the higher band.

For example, communication device 1904 may desire to communicate withcommunication device 1910 using the higher band, but may not be able toestablish a direct link 1930 in the higher band for any of a number ofreasons (e.g., signal is blocked by a structure 1934), where a failureto establish the direct link 1930 is indicated by 1932. In such ascenario, the communication device 1904 can, for example, notify thecoordinating device 1902 that the communication device 1940 wants toestablish higher band communication with the communication device 1910.The coordinating device 1902 can use the connectivity table/schedule toarrange data transmission from the communication device 1940 to thecommunication device 1910 using, for example, the higher bandcommunication links 1920, 1922, 1924 of communication devices 1906 and1908 to relay the information.

The coordinating device 1902 may arrange particular time and/orfrequency resources for higher band link establishment between thecommunication devices (e.g., 1904, 1906, 1908, 1910) to avoidinterference. For example, a pair of communication devices may varydirections/positions of their respective antenna systems as part of alink establishment search routine, which may produce substantialinterference on higher band transmissions of other communicationdevices. The coordinating device 1902 may avoid such interference byallocating time intervals for higher band communication between pairs ofcommunications devices.

The coordinating device 1902 may further arrange interferencemeasurements by the communication devices using the higher band. Forexample, the interference measurements can be performed by thecommunication devices during the assigned time interval to determinelink availability in the higher band. The connectivity table may includean interference level that a higher band link produces on other higherband links and/or corresponding throughput degradation experienced bythe higher band links.

Based on the interference information, the coordinating device 1902 candetermine/calculate a more efficient schedule of transmissions in thehigher band by the communication devices. The coordinating device 1902may, for example, allow simultaneous transmissions for links that havelower mutual interference and/or prevent simultaneous transmissions forlinks that have higher mutual interference. The coordinating device 1902may determine lower and higher mutual interference by comparing thereceived interference levels and/or corresponding throughput degradationto one another or to a pre-determined threshold interference/degradationlevel. Such scheduling of transmissions based on interferenceinformation may increase aggregate throughput of information in thecommunication system 1900.

Using the lower band, the coordinating device 1902 may transmit atransmission schedule for communication in the higher band by thecommunication devices (e.g., 1904, 1906, 1908, 1910) to thecommunication devices. The coordinating device 1902 may, for example,broadcast a message to simultaneously notify the communication devicesof the transmission schedule.

The communication devices (e.g., 1904, 1906, 1908, 1910) may performlink establishment procedures for the higher band using only the higherband. For example, an initiating communication device may perform asearch routine in accordance with a transmission schedule received fromthe coordinating device 1902. The search routine may include, forexample, transmission of test signal(s) such as preamble/pilot signalsusing the higher band and repositioning of beams of transceivers. Areceiving communication device may receive the test signal(s) anddetermine whether a link quality in the higher band is sufficient and/ormake beam adjustments to improve link quality. Further test signals maybe transmitted by the initiating communication device using the higherband to facilitate carrier frequency offset (CFO), timingsynchronization, and fine beam-forming adjustments in the higher band.Once a link is established in the higher band between the initiatingcommunication device and the receiving communication device, one or bothof the initiating and receiving communication devices may notify thecoordinating device 1902 about the newly established link.

According to various embodiments, the coordinating device 1902 is acommunication device having circuitry in accordance with embodimentsdescribed, for example, in FIGS. 6-7. In an embodiment, the coordinatingdevice 1902 is an access point (AP) for wireless communication networkin accordance with IEEE 802.11 (e.g., Wi-Fi), but is not limited in thisregard. The coordinating device 1902 may be an AP that operatesaccording to other wireless technologies.

The coordinating device 1902 may be connected with a computer networksuch as the Internet (e.g., 1950) by a line 1940 such as a wire oroptical fiber. In other embodiments, the coordinating device 1902 may beconnected with the computer network (e.g., 1950) by a wireless link (notshown). In an embodiment, the coordinating device 1902 seeks toestablish higher band links with communication devices of thecommunication system 1900 either directly (e.g., links 1926, 1928) orthrough communication devices operating as relays to increase throughputfor the communication system 1900.

The coordinating device 1902 may include a coordinating module to createthe connectivity table based on received link availability informationand/or interference information and a scheduling module to create atransmission schedule based on the connectivity table and/or informationassociated with the connectivity table. As used herein, the term“module” may refer to, be part of, or include an Application SpecificIntegrated Circuit (ASIC), an electronic circuit, a processor (shared,dedicated, or group) and/or memory (shared, dedicated, or group) thatexecute one or more software or firmware programs, a combinational logiccircuit, and/or other suitable components that provide the describedfunctionality.

FIG. 20 illustrates a process 2000 for coordinating communication by acoordinating device (e.g., 1902) in a wireless network in accordancewith various embodiments. The actions/operations described in connectionwith the process 2000 may be performed, for example, by a coordinatingdevice (e.g., 1902). At block 2002, the process 2000 includestransmitting in a first frequency band (e.g., lower band) an indicationof a time/frequency resource for a communication device to identify oneor more neighbor communication devices that are capable of communicatingover a second frequency band.

The time/frequency resource may, for example, include a time intervalfor the communication device to identify, using the second frequencyband or another frequency band other than the first or second frequencyband, the one or more neighbor communication devices that are capable ofcommunicating over the second frequency band. In an embodiment, theindicated time/frequency resource includes a dedicated frequency channel(e.g., second frequency band or other frequency interval). For example,if a frequency boundary is indicated or specified, the time/frequencyresource may include a time interval and if a time boundary is indicatedor specified, the time/frequency resource may include a frequencyinterval such as a channel, band or one or more subcarriers (which are afraction of a channel or band) when the system is using OFDM modulation.

At block 2004, the process 2000 includes receiving, in the firstfrequency band, link availability information and/or interferenceinformation for the second frequency band. The link availabilityinformation and/or interference information may be received from thecommunication device. A connectivity module that is part of or coupledto the coordinating device may create a connectivity table having, forexample, pairs of communication devices that are capable of directlycommunicating using the second frequency band. The connectivity tablemay be based on link availability information and/or interferenceinformation obtained by the communication device.

In an embodiment, receiving interference information includes receivinginterference measurements performed by the communication device such asan indication of an interference level(s). The interference measurementsmay be performed by one or more communication devices, including thecommunication device. The interference information may includeinformation indicative of a source of the interference such as anidentification of a particular station or direction associated with theinterference. The coordinating device may distribute such interferenceinformation to facilitate correction of the interference (e.g., byadjusting antenna position of affected receivers/transmitters). The linkavailability information and/or the interference information for thesecond frequency band may be obtained during the indicatedtime/frequency resource (e.g., the time resource being a time intervaland the frequency resource being the second frequency band) to identifythe one or more neighbor communication devices that are capable ofcommunicating over the second frequency band.

At block 2006, the process 2000 includes determining a transmissionschedule for the communication device to communicate in the secondfrequency band. The transmission schedule may be determined based atleast in part on the received interference information. In anembodiment, the transmission schedule is determined at least in part bycomparing the interference levels to allow simultaneous transmission forat least two communication devices that have mutual interference levelsbelow a threshold level using the second frequency band and to preventsimultaneous transmission for at least another two communication devicesthat have mutual interference levels above the threshold level using thesecond frequency. The transmission schedule may be determined by ascheduling module that is either part of or coupled to the coordinatingdevice and may be based at least in part on the received linkavailability information and/or interference information.

For example, consider an example where a transmitting communicationdevice seeks to transmit to a receiving communication device with aninterfering communication device (e.g., a transmission from theinterfering communication device may interfere with reception of asignal by the receiving communication device from the transmittingcommunication device). If the interfering communication device createsan interference level on the receiving communication device that isbelow a predetermined threshold, e.g., as compared by the coordinatingdevice or module having similar functionality coupled to thecoordinating device, the coordinating device may allow simultaneoustransmission of the transmitting communication device to the receivingcommunication device and the interfering communication device to, e.g.,another communication device. If the interfering communication devicecreates an interference level on the receiving communication device thatis above a predetermined threshold, then the coordinating device mayprevent simultaneous transmission of the transmitting communicationdevice to the receiving communication device and the interferingcommunication device to, e.g., the other device.

At block 2008, the process 2000 includes transmitting, in the firstfrequency band, a transmission schedule to indicate a time/frequencyresource in which the communication device can communicate with at leastone of the one or more neighboring communication devices over the secondfrequency band. The time/frequency resource may include a time period ora particular frequency interval, or combinations thereof. For example,the coordinating device may schedule a frequency subchannel or multipletime slots/frequency subchannels for communication using the secondfrequency band.

The transmission schedule may be transmitted, for example, by a beacontransmission to all communication devices within range to receive thebeacon transmission. In other embodiments, the transmission schedule maybe distributed to the communication devices by other means such asunicast messaging (e.g., polling).

At block 2010, the process 2000 includes receiving notification ofestablishment of a communication link, the communication link being overthe second frequency band and being between the communication device andat least one of the one or more neighboring communication devices. Thenotification may be received, for example, by one or both of thecommunication device and the other linked communication device using anysuitable frequency band.

FIG. 21 illustrates a process 2100 for coordinating communication by acommunication device (e.g., 1904) in a wireless network in accordancewith various embodiments. The actions/operations described in connectionwith the process 2100 may be performed, for example, by a communicationdevice (e.g., 1904). At block 2102, the process 2100 includes receiving,in a first frequency band, an indication of a time/frequency resourcefor the communication device to identify one or more neighborcommunication devices that are capable of communicating over a secondfrequency band. The indication of the time/frequency resource may bereceived from a coordinating device (e.g., 1902). The time/frequencyresource may comport with embodiments already described in connectionwith at least FIG. 20.

At block 2104, the process 2100 includes identifying, using theindicated time/frequency resource, one or more neighboring communicationdevices that are capable of communicating over the second frequencyband. Said identifying may include transmitting search routine signalsassociated with link establishment as described herein.

At block 2106, the process 2100 includes transmitting, in the firstfrequency band, link availability information and/or interferenceinformation of the one or more neighboring communication devices thatare capable of communicating over the second frequency band. Saidtransmitting of interference information may include, for example,interference measurements including interference levels, theinterference measurements being performed by one or more communicationdevices, including the communication device.

At block 2108, the process 2100 includes receiving, in the firstfrequency band, a transmission schedule to indicate a time/frequencyresource in which the communication device can communicate with at leastone of the one or more neighboring communication devices over the secondfrequency band. The transmission schedule may be based, for example, onthe transmitted link availability and/or interference information. Thetime/frequency resource may comport with embodiments already describedin connection with at least FIG. 20.

At block 2110, the process 2100 includes transmitting a notificationthat a communication link is established over the second frequency bandbetween the communication device and at least one of the one or moreneighboring communication devices. The notification may be transmittedby one or both of the communication device and the other linkedcommunication device.

FIG. 22 illustrates a system 2200 with two different types of wirelesscommunication systems 2240, 2250 operating in different frequency bands,with each frequency band having a different beamwidth and correspondingadvantages, as previously described. In general, the communicationsystem 2240 may utilize a wider beamwidth 2210 having a larger coveragearea and lower throughput suitable for control information, and thecommunication system 2250 may utilize a narrower beamwidth 2220 having asmaller coverage area and higher throughput suitable for datainformation, although both beamwidths 2210, 2220 may be used tocommunicate both control information and data information at varyinglevels of performance. The wireless communication systems 2240, 2250 areparticularly suitable for outdoor operating environments, such as abroadband wireless personal area network (WPAN), wireless video areanetwork (WVAN), wireless local area network (WLAN), wirelessmetropolitan area network (WMAN), a wireless wide area network (WWAN),and so forth. Although system 2200 illustrates only two wirelesscommunication systems 2240, 2250 for clarity, it may be appreciated thatmore than two wireless communication systems may be utilized in someembodiments. Furthermore, although system 2200 illustrates two wirelesscommunication systems 2240, 2250, it may be appreciated that the systems2240, 2250 may be combined into a single wireless system operating inaccordance with a single unified standard, such as a fifth generation(5G) standard, for example.

System 2200 comprises a first communication system 2240. The firstcommunication system 2240 may comprise a cellular radio network. Thecellular radio network may have one or more base stations 2204. Eachbase station 2204 may service a cell 2212 in the cellular radio networkby transmitting RF electromagnetic signals in a certain beamwidth 2210.Each base station 2204 may further support multi-carrier operations andtherefore may communicate with mobile stations, such as user equipment(UE) 2202, on various carrier frequencies. In a fourth generation (4G)wireless standard, such as the Institute of Electrical and ElectronicsEngineers (IEEE) 802.16m, 802.16p, and the 3rd Generation PartnershipProject (3GPP) Long Term Evolution (LTE) and LTE Advanced (LTE ADV)standards, multi-carrier operation may support larger bandwidths andmeet International Mobile Telecommunications Advanced (IMT-ADV)specifications for system capacity. Each base station 2204 in a networkmay use different carrier frequencies. The base stations may beconfigured with different carrier frequencies according to factors suchas, but not limited to, the available technology and regional marketdemand.

In one embodiment, for example, the communications system 2240 may beimplemented by any communication system operating using a frequency bandlower than 10 GHz, such as a 3GPP LTE or LTE ADV system, among others.3GPP LTE and LTE ADV are standards for wireless communication ofhigh-speed data for mobile phones and data terminals. They are based onGlobal System for Mobile Communications (GSM)/Enhanced Data Rates forGSM Evolution (EDGE) and Universal Mobile Telecommunications System(UMTS)/High Speed Packet Access (HSPA) technologies, increasing capacityand speed using new modulation techniques. Alternatively, thecommunication system 2240 may be implemented in accordance with theWorldwide Interoperability for Microwave Access (WiMAX) or the WiMAX IIstandard, among others. WiMAX is a wireless broadband technology basedon the IEEE 802.16 series of standards. WiMAX II is an advanced FourthGeneration (4G) system based on the IEEE 802.16m and IEEE 802.16j seriesof standards for International Mobile Telecommunications (IMT) Advanced4G series of standards. Although some embodiments may describe thecommunications system 2240 as a LTE, LTE ADV, WiMAX or WiMAX II systemor standards by way of example and not limitation, it may be appreciatedthat the communications system 2240 may be implemented as various othertypes of mobile broadband communications systems and standards, such asa Universal Mobile Telecommunications System (UMTS) system series ofstandards and variants, a Code Division Multiple Access (CDMA) 2000system series of standards and variants (e.g., CDMA2000 1.times.RTT,CDMA2000 EV-DO, CDMA EV-DV, and so forth), a High Performance RadioMetropolitan Area Network (HIPERMAN) system series of standards ascreated by the European Telecommunications Standards Institute (ETSI)Broadband Radio Access Networks (BRAN) and variants, a WirelessBroadband (WiBro) system series of standards and variants, a GlobalSystem for Mobile communications (GSM) with General Packet Radio Service(GPRS) system (GSM/GPRS) series of standards and variants, an EnhancedData Rates for Global Evolution (EDGE) system series of standards andvariants, a High Speed Downlink Packet Access (HSDPA) system series ofstandards and variants, a High Speed Orthogonal Frequency-DivisionMultiplexing (OFDM) Packet Access (HSOPA) system series of standards andvariants, a High-Speed Uplink Packet Access (HSUPA) system series ofstandards and variants, 3rd Generation Partnership Project (3GPP) Rel. 8and 9 of Long Term Evolution (LTE)/System Architecture Evolution (SAE),LTE ADV, and so forth. The embodiments are not limited in this context.

System 2200 comprises a second communication system 2250. Thecommunication system 2250 may also comprise a cellular radio networkdifferent from the communication system 2240. The cellular radio networkmay have one or more base stations 2208. As with base stations 2204,each base station 2208 may service a cell 2222 in the cellular radionetwork by transmitting RF electromagnetic signals having a certainbeamwidth 2220. Further, each base station 2208 may supportmulti-carrier operations and therefore may communicate with mobilestations, such as user equipment (UE) 2202, on various carrierfrequencies. Examples for communication system 2250 may include withoutlimitation any communication system operating using a frequency bandgreater than 10 GHz, such as millimeter-wave (mmWave) systems. Examplesof mmWave systems may include without limitation a system as defined byone or more Wireless Gigabit Alliance (WiGig) series of specifications,IEEE 802.11ad series of specifications, IEEE 802.15 series ofspecifications, and other 60 GHz mmWave wireless systems. Anotherexample for communication system 2250 may include a Local MultipointDistribution Service (LMDS) system operating in the 28 GHz and 31 GHzfrequency bans. The embodiments are not limited in this context.

In one embodiment, the communication system 2240 operates in a firstfrequency band, and the communication system 2250 operates in a secondfrequency band, with the first frequency band lower than the secondfrequency band. The communication system 2240 and the first frequencyband may be associated with a first beamwidth 2210, while thecommunication system 2250 and the second frequency band may beassociated with a second beamwidth 2220. In one embodiment, the firstbeamwidth 2210 may be broader or greater than the second beamwidth 2220.In one embodiment, the first beamwidth 2210 may be narrower or smallerthan the second beamwidth 2220. In one embodiment, the first and secondbeamwidths 2210, 2220 may have a same beamwidth. It is worthy to notethat both systems 2240, 2250 may use beamforming techniques that mayadjust beamwidths 2210, 2220, respectively, on an instantaneous basis,and therefore beamwidths may be compared for a given time instance, anaverage beamwidth, or other statistical measurement.

The first frequency band may be lower than the second frequency band.For instance, the first frequency band may have a center frequency ofless than 10 GHz, and the second frequency band may have a centerfrequency of more than 10 GHz. More particularly, the first frequencyband may comprise one or more frequencies within a 700 MHz to 2.5 GHzrange, as used in the 3GPP LTE and LTE ADV standards, among others. Thesecond frequency band may comprise one or more frequencies within a 59GHz to 62 GHz range, as used in the IEEE 802.11ad standard, and the 28GHz to 31 GHz range, as used in the LMDS standard, among others. Theembodiments are not limited to these examples.

The base stations 2204, 2208 may be connected to a core network 2230.The core network 2230 may include, for example, the coordinating device1902 as described with reference to FIG. 19 and a control entity 2290.The control entity 2290 may include logic to coordinate interoperabilitybetween the communication systems 2240, 2250, such as a establishing andmanaging a frame synchronization period common to both systems, asdescribed further below.

The communication systems 2240, 2250 may communicate with one or moreuser equipment 2202. User equipment 2202 may comprise a mobile or fixedwireless device. The user equipment 2202 may comprise various wirelessinterfaces and/or components to support wireless communication, such asone or more radios, transmitters, receivers, transceivers, chipsets,amplifiers, filters, control logic, network interface cards (NICs),antennas, antenna arrays, and so forth. Examples of an antenna mayinclude, without limitation, an internal antenna, a directional antenna,an omni-directional antenna, a monopole antenna, a dipole antenna, anend fed antenna, a circularly polarized antenna, a micro-strip antenna,a diversity antenna, a dual antenna, an antenna array, and so forth.Certain devices may include antenna arrays of multiple antennas toimplement various adaptive antenna techniques and spatial diversitytechniques. In various embodiments, user equipment 2202 may comprise oneor more RF antennas coupled to receiver circuitry to receiveelectromagnetic representations of the first, second, and/or thirdsignals, as previously defined. In one embodiment, for example, userequipment 2202 may comprise one or more omni-directional antennascoupled to receiver circuitry to receive electromagnetic representationsof the first signals. In one embodiment, for example, user equipment2202 may comprise one or more directional antennas coupled to receivercircuitry to receive electromagnetic representations of the second andthird signals.

Examples of user equipment 2202 may include, without limitation, astation, a subscriber station, a mobile station, a wireless clientdevice, a wireless station (STA), a laptop computer, ultra-laptopcomputer, portable computer, personal computer (PC), notebook PC,handheld computer, personal digital assistant (PDA), cellular telephone,combination cellular telephone/PDA, smart phone, tablet computer, pager,messaging device, media player, digital music player, set-top box (STB),appliance, workstation, user terminal, mobile unit, consumerelectronics, television, digital television, high-definition television,television receiver, high-definition television receiver, and so forth.The embodiments are not limited in this context.

The user equipment 2202 may each include or implement a dual-band radioarchitecture having one or more co-located radios capable ofcommunicating information using different frequency bands. Each wirelessdevice may have a radio architecture utilizing multiple radiosco-located within the single wireless device, with each radio operatingat a different frequency band corresponding to the first and secondfrequency bands used by the first and second communication systems 2240,2250, respectively. A control element, such as a controller, may beimplemented to coordinate and synchronize operations between themultiple co-located radios. Specific radios and corresponding operatingfrequency bands for a given implementation may be selected in accordancewith the advantages of a given radio to perform media operations orcontrol operations. Combining the advantages of multiple co-locatedradios within a single wireless device may enhance the overallcommunications capabilities for a wireless device. Alternatively, theuser equipment 2202 may utilize a single radio capable of operating inmultiple frequency bands. The embodiments are not limited in thiscontext.

FIG. 23 illustrates an exemplary embodiment of user equipment 2202arranged for wireless communication with different types ofcommunication systems, such as communication systems 2240, 2250. Inparticular, FIG. 23 shows user equipment 2202 comprising variouselements. The embodiments, however, are not limited to these depictedelements. FIG. 23 shows that user equipment 2202 may include a firstradio module 2302 coupled to a set of one or more antennas 2310, asecond radio module 2304 coupled to a set of one or more antennas 2350,a host processor 2306, and an interconnection medium 2308 to couple thehost processor 2306 with the first and second radio modules 2302, 2304.These elements may be implemented in hardware, software, firmware, or inany combination thereof.

Although user equipment 2202 only shows two radio modules 2302, 2304, itmay be appreciated that user equipment 2202 may include more than tworadio modules (and associated elements) as desired for a givenimplementation. Further, although user equipment 2202 illustratesseparate sets of antennas 2310, 2350 for each of the first and secondradio modules 2302, 2304, respectively, it may be appreciated that theradio modules 2302, 2304 may share one or more antennas from a singleantenna array via some form of shared antenna structure. The embodimentsare not limited in this context.

First radio module 2302 and second radio module 2304 (and/or additionalradio modules) may communicate with remote devices across differenttypes of wireless links. For example, first radio module 2302 and secondradio module 2304 may communicate across various data networking linkswith the base stations 2204, 2208, respectively. In one embodiment, forexample, first radio module 2302 is a 3GPP LTE or LTE ADV device andsecond radio module 2304 is a mmWave device, such as an IEEE 802.11 addevice. The embodiments, however, are not limited to these examples.

FIG. 23 shows that first radio module 2302 includes a transceiver 2314and a communications controller 2316. Transceiver 2314 may transmit andreceive wireless signals through one or more antennas 2310. As describedabove, these signals may be associated with wireless data networks, suchas a 3GPP LTE or LTE ADV link. However, the embodiments are not limitedto such.

Communications controller 2316 controls the operation of transceiver2314. For instance, communications controller 2316 may scheduletransmission and reception activity for transceiver 2314. Such controland scheduling may be implemented through one or more control directives2326. Control directive(s) 2326 may be based on operational statusinformation 2328, which communications controller 2316 receives fromtransceiver 2314. Also, such control directives may be based on statusmessages and/or commands 2336 received from radio module 2304. Theembodiments, however, are not limited to these examples.

Further, communications controller 2316 may perform operations onpayload information 2329 that it exchanges with transceiver 2314.Examples of such operations include error correction encoding anddecoding, packet encapsulation, various media access control protocolfunctions, and so forth.

As shown in FIG. 23, second radio module 2304 includes a transceiver2318 and a communications controller 2320. Transceiver 2318 may alsotransmit and/or receive wireless signals through one or more antennas2350. As described above, these signals may also be associated withwireless data networks, such as an IEEE 802.11ad link. However, theembodiments are not limited to such.

Communications controller 2320 controls the operation of transceiver2318. This may involve scheduling transmission and reception activityfor transceiver 2318. Such control and scheduling may be implementedthrough one or more control directives 2322. Control directive(s) 2322may be based on operational status information 2324, whichcommunications controller 2320 receives from transceiver 2318. Also,such control directives may be based on status messages and/or commands2334 received from radio module 2302. The embodiments, however, are notlimited to these examples.

Additionally, communications controller 2320 may perform operations onpayload information 2325 that it exchanges with transceiver 2318.Examples of such operations include error correction encoding anddecoding, packet encapsulation, various media access control protocolfunctions, and so forth.

In addition to performing the control operations described above,communications controllers 2316, 2320 may provide coordination betweenradio modules 2302, 2304. This coordination may involve the exchange ofinformation. For instance, FIG. 23 shows that communications controller2316 may send status messages and/or commands 2334 to controller 2320.Conversely, communications controller 2320 may send status messagesand/or commands 2336 to communications controller 2316. These messagesmay be implemented as signals allocated to various signal lines. In suchallocations, each message is a signal. However, further embodiments mayalternatively employ data messages. Such data messages may be sentacross various connections. Exemplary connections include parallelinterfaces, serial interfaces, and bus interfaces. Further, as systemson a chip (SoC) develop, the separate communication controllers 2316,2320 may in fact be the same piece of silicon or the same coreprocessor. The communication controllers 2316, 2320 may actually bedifferent function calls or software modules operating on the same chip.In that case, the messages may not use different physical connectionssuch as parallel interfaces, serial interfaces, or bus interfaces. Whenthe functions collapse into one chip, these messages may be passed asmessage queues, shared via stacks, sent via semaphores or flags, and soforth. The embodiments are not limited in this context.

Host processor 2306 may exchange information with radio modules 2302,2304. As shown in FIG. 23, such exchanges may occur acrossinterconnection medium 2308. For instance, host processor 2306 may sendinformation to these radio modules for wireless transmission.Conversely, radio modules 2302 and 2304 may send information to hostprocessor 2306 that was received in wireless transmissions. In addition,host processor 2306 may exchange information with radio modules 2302 and2304 regarding their configuration and operation. Examples of suchinformation include control directives sent from host processor 2306 toradio modules 2302, 2304.

Interconnection medium 2308 provides for couplings among elements, suchas first radio module 2302, second radio module 2304, and host processor2306. Thus, interconnection medium 2308 may include, for example, one ormore bus interfaces. Exemplary interfaces include Universal Serial Bus(USB) interfaces, Serial Peripheral Interconnect (SPI) interfaces,Secure Digital Input Output (SDIO) interfaces, as well as variouscomputer system bus interfaces. Additionally or alternatively,interconnection medium 2308 may include one or more point-to-pointconnections (e.g., parallel interfaces, serial interfaces, etc.) betweenvarious element pairings. In some cases, the host processor 2306 may bein the same physical chip as the communication controllers 2316, 2320.The interconnection medium 2308 may therefore be software rather than aphysical interface such as USB, SDIO, SPI, bus, parallel, and so forth.As such cases, the interconnection medium 2308 may be implemented asmessage queues, semaphores, function calls, stack, global variables,pointers, and so forth. The embodiments are not limited in this context.

In various embodiments, the transceivers 2314, 2318 of the userequipment 2202 may include transmitter circuitry and/or receivercircuitry, such as transmitter circuitry 2380, 2386 and/or receivercircuitry 2382, 2388 of the transceivers 2314, 2318, respectively. Thetransmitter circuitry 2380, 2386 and the receiver circuitry 2382, 2388may be the same or similar to the transmitter circuitry 702, 1202 andthe receiver circuitry 704, 1204 as described with reference tocircuitry 700, 1200, respectively, in FIGS. 7, 12, respectively. It maybe appreciated that references to a specific transmitter circuitry orreceiver circuitry may be applicable to other types of transmittercircuitry or receiver circuitry as described herein. For instance, someembodiments for the user equipment 2202 may be described with referenceto the receiver circuitry 2382 or the receiver circuitry 2388, althoughother embodiments may use any of the receiver circuitry 704, 1204, 2382or 2388. The embodiments are not limited in this context.

In one embodiment, the transceivers 2314, 2318 of the user equipment2202 may include receiver circuitry 2382, 2388 coupled to processorcircuitry. Examples of processor circuitry may include withoutlimitation communications controllers 2316, 2320, host processor 2306,processor circuitry 2390 of the host processor 2306, and otherprocessing devices, circuits or architectures.

In the illustrated embodiment shown in FIG. 23, the receiver circuitry2382 may be arranged to receive first signals in a first frequency bandassociated with a first beamwidth 2210. The receiver circuitry 2388 maybe arranged to receive second signals in a second frequency bandassociated with a second beamwidth 2220. The first signals may bereceived from the base station 2204 and comprise, for example, controlinformation which includes a frame synchronization parameter. The secondsignals may be received from the base station 2208 and comprise, forexample, control information which includes frame alignment signals.

It is worthy to note that although some embodiments are described withthe base station 2204, the base station 2208 and the user equipment 2202exchanging a frame synchronization parameter for frame alignmentoperations during real-time operations, it may be appreciated that theframe synchronization parameter may be a standardized element in awireless standard and may be implemented by the communications systems2240, 2250, the base stations 2204, 2208, and the user equipment 2202during a design and manufacture stage of each of these elements.Additionally or alternatively, the frame synchronization parameter maybe distributed to the communications systems 2240, 2250, the basestations 2204, 2208, and the user equipment 2202 during initializationoperations for each of these elements. The embodiments are not limitedin this context.

The processor circuitry 2390 may be arranged to activate or deactivatethe receiver circuitry 2382, 2388 to receive the frame alignment signalsbased on the frame synchronization parameter. Once the frame alignmentsignals are detected, the processor circuitry may activate the receivercircuitry 2388 to receive third signals in the second frequency band,the third signals comprising payload data.

A frame synchronization parameter may be used for timing synchronizationbetween communication frames (or frames) in the communication systems2240, 2250. A frame synchronization parameter represents a defined timeinterval, such as a frame synchronization period (or system period),selected so that typical timing scales in both the communication system2240 (e.g., first frequency band or lower frequency band) and thecommunication system 2250 (e.g., second frequency band or upperfrequency band) are integer multiples or fractions of the selected framesynchronization period.

The control entity 2290 of the core network 2230 may automaticallyestablish an initial frame synchronization parameter for thecommunication systems 2240, 2250, and dynamically update the framesynchronization parameter in response to changes in operating conditionsfor the communication systems 2240, 2250 or user instructions (e.g., asystem provider or administrator). Alternatively, a user such as asystem provider or system administrator may define the framesynchronization parameter, and enter the defined frame synchronizationparameter into the control entity 2290 to store, propagate and manage onbehalf of the communication systems 2240, 2250. The embodiments are notlimited in this context.

FIG. 24 illustrates a timing diagram 2400 with a frame synchronizationperiod 2410 common for two different types of wireless communicationsystems 2240, 2250. As shown in FIG. 24, one or more communicationframes 2412 (e.g., radio frames) may be communicated between the basestation 2204 of the communication system 2240 and the user equipment2202 in a first frequency band 2402. Further, one or more communicationframes 2416 (e.g., radio frames) may be communicated between the basestation 2208 of the communication system 2250 and the user equipment2202 in a second frequency band 2404.

Normally, when receiving a stream of framed data, the user equipment2202 may perform frame synchronization operations. Frame synchronizationis the process by which incoming frame alignment signals are identified,permitting the data bits within the frame to be extracted for decodingor retransmission. This process is sometimes referred to as “framing.”Frame alignment signals are distinctive bit sequences and/or distinctwaveforms used to synchronize a transmission by indicating the end ofheader information (e.g., control information or control bits) and thestart of data (e.g., data information or data bits). In other words,frame alignment signals allow the user equipment 2202 to distinguishcontrol bits from data bits in a stream of framed data. Examples offrame alignment signals may include without limitation a syncword, synccharacter, beacon, preamble, space of a defined length in a frame,self-synchronizing code, framing bit, non-information bit, and so forth.In some cases, frame alignment signals may be sent simultaneously withdata bits, such as in OFDM modulation, for example. In such cases, thetiming of frame alignment signals with respect to data bits ispredefined and may be fixed, which allows indicating the timing of databits via the frame alignment signals. The embodiments are not limited inthis context.

A problem occurs, however, when attempting to perform framesynchronization using multiple communication systems 2240, 2250. Oneadvantage of a dual-mode communication system such as the communicationsystem 2200 is that the first frequency band 2402 of the communicationsystem 2240 may be used for OOB signaling to rapidly acquire andestablish a communication channel between the communication system 2250and the user equipment 2202 over the second frequency band 2404 forhigh-speed data communications, such as high-definition (HD) video, forexample. However, before acquiring second or third signals from the basestation 2208 of the communication system 2250, the user equipment 2202needs to detect frame alignment signals, such as beacons, transmitted inthe second frequency band 2404. Since the user equipment 2202 does nothave any a priori knowledge of when frame alignment signals are to betransmitted by the base station 2208, the receiver circuitry 2382 (or2388) needs to continuously scan the second frequency band 2404 in orderto detect the frame alignment signals. The extensive scanning operationsby the receivers consume significant amounts of power, which is a scarceresource for mobile devices. Furthermore, frames 2412, 2416 of thecommunication systems 2240, 2250, respectively, are not necessarilyaligned. Therefore, the user equipment 2202 cannot use known timingassociated with frames 2412 in the first frequency band 2402 to estimatetiming associated with frames 2416 in the second frequency band 2404.This problem is further exacerbated in the case where multiple mmWavesystems (e.g., multiple communication systems 2250) are used sinceadditional operations are needed to determine which mmWave signals aredetected, which consumes even greater amounts of power.

To solve these and other problems, the control entity 2290 may establishand store a frame synchronization period 2410 that may be used tosynchronize frames 2412, 2416 transmitted in the frequency bands 2402,2404, respectively. The control entity 2290 may define, generate,select, or otherwise establish a frame synchronization period 2410. Theframe synchronization period 2410 may then be used to set timing scalesin both the communication system 2240 (e.g., first frequency band orlower frequency band) and the communication system 2250 (e.g., secondfrequency band or upper frequency band) that are integer multiples orfractions of the selected frame synchronization period 2410.

The processor circuitry 2390 of the user equipment 2202 may receivefirst signals from the first communication system 2240 associated withthe first beamwidth 2210. The first signals may include a framesynchronization parameter 2410. A frame synchronization parameter 2410may comprise or represent a reference time interval for the secondcommunication system 2250 associated with the second beamwidth 2220. Anexample of a reference time interval may comprise a framesynchronization period 2418. In one embodiment, for example, thereference time interval is equally divisible by one or more frames 2412of the first communication system 2240 associated with the firstbeamwidth 2210.

In one embodiment, the control entity 2290 may set a framesynchronization period 2410 to a beacon interval 2418 of a mmWavecommunication system, such as the second communication system 2250, forexample. The beacon interval 2418 is a time interval between beaconframes transmissions, and is configurable for various systems. Aparticular beacon interval 2418 may be selected or configured to beequally divisible by one or more frames 2412 of a cellular communicationsystem, such as the first communication system 2240, for example. Forinstance, assume the beacon interval 2418 is set to 100 milliseconds(ms) for the second communication system 2250. The 100 ms is equallydivisible into 10 radio frames 2412 of the first communication system2240, where one radio frame T_(f)=307200T_(s)=10 ms, and one half-frame153600T_(s)=5 ms. It may be appreciated that other definitions for theframe synchronization period 2410 with respect to different time scalesof the protocols in the first frequency band 2402 (e.g., lower band) andthe second frequency band 2404 (e.g., upper band) are also possible. Theembodiments are not limited in this context.

FIG. 25 illustrates a timing diagram 2500 to synchronize frames from twodifferent types of wireless communication systems 2240, 2250 using aframe synchronization period 2418. As previously described, the userequipment 2202 may utilize a frame synchronization parameterrepresenting a frame synchronization period 2418 to synchronize frames2412, 2416 transmitted in the frequency bands 2402, 2404, respectively.As a result, the frames 2412, 2416 transmitted by the communicationsystems 2240, 2250, respectively, are aligned. As such, the userequipment 2202 can use known timing associated with frames 2412 in thefirst frequency band 2402 to accurately estimate or predict timingassociated with frames 2416 in the second frequency band 2404. Toconserve power, the user equipment 2202 may activate or deactivate thereceiver circuitry 2388 of the transceiver 2318 of the second radiomodule 2304 to detect and receive the frame alignment signals as theyare scheduled to arrive, thereby reducing power consumption for the userequipment 2202.

The timing diagram 2500 further illustrates this technique. As shown inFIG. 25, the timing diagram illustrates two different types of signalstransmitted by the second frequency band 2404. The first type of signalis a beacon 2502. The second type of signal is a payload data 2504. Theprocessor circuitry 2390 of the user equipment 2202 may activate thereceiver circuitry 2388 (or 2382) of the transceiver 2318 of the secondradio module 2304 to detect and receive the beacons 2502 during a beacontransmission interval 2510. The processor circuitry 2390 may deactivatethe receiver circuitry 2388 (or 2382) during a time interval defined bythe frame synchronization parameter to conserve power, that is, thebeacon interval where no beacons 2502 are transmitted. By way ofcontrast, conventional solutions would cause the receiver circuitry 2388(or 2382) to be continuously active to detect and acquire a beacon 2502.In this manner, the user equipment 2202 may utilize power moreefficiently, thereby extending battery life for the user equipment 2202.

FIG. 26 illustrates an operating environment 2600 to detect framealignment signals using a frame synchronization period 2418. In theillustrated embodiment shown in FIG. 26, a frame synchronizer module2606 may receive as input a frame synchronization parameter 2602 and oneor more operating parameters 2604. The operating parameters 2604 may beused to provide information needed by the frame synchronizer module 2606to begin synchronizing frames 2412, 2416, such as N number of lastreceived frames 2412, a counter value, a timer value, and so forth. Theframe synchronizer module 2606 may comprise computer programinstructions that when executed by the processor circuitry 2390 causesthe frame synchronizer module 2606 to output control directives 2608.The control directives 2608 may be of at least two types, including afirst type to activate receiver circuitry 2388 (or 2382) and a secondtype to deactivate receiver circuitry 2388. Deactivation may includevarious power states ranging from a fully power state to completelypowered down state, such as defined by the Advanced Configuration andPower Interface (ACPI) specification. The ACPI specification provides anopen standard for device configuration and power management by anoperating system (OS) of the user equipment 2202. The frame synchronizermodule 2606 may send the control directives 2608 to the radio modules2302, 2304, as appropriate.

FIG. 27 illustrates a process 2700 for controlling a wireless receiverto detect frame alignment signals using a frame synchronization period2418. The actions/operations described in connection with the process2700 may be performed, for example, by a user device 2202.

At block 2702, the process 2700 includes activating a first receiver,such as the receiver portion of the transceiver 2314 as described withreference to FIG. 23. For instance, when the user equipment 2202 entersthe cell 2212 of the first communication system 2240, it begins toreceive control signals from the base station 2204. The user equipment2202 may activate the receiver circuitry 2382 of the transceiver 2314 ofthe first radio module 2302 to establish a communication channel betweenthe base station 2204 and the user equipment 2202. At some point, theuser equipment 2202 may continue moving within the cell 2212 until itenters the cell 2222 of the second communication system 2250. At thispoint, the user equipment 2202 is within transmission range of both basestations 2204, 2208.

At block 2704, the process 2700 includes receiving first signals in afirst frequency band associated with a first beamwidth. For instance,when the user equipment 2202 enters the cell 2212, it may beginreceiving control signals from the base station 2204 over the firstfrequency band 2402 with information to assist in pre-configuring theuser equipment 2202 for establishing a communication channel with thesecond communication system 2250 using the second frequency band 2404.The information may be used for signal detection, coarse beamforming,CFO estimation, timing synchronization, and other operations useful inacquiring signals from the base station 2208.

At block 2706, the process 2700 includes retrieving timing informationfrom the first signals, the timing information to indicate when todetect second signals in a second frequency band associated with asecond beamwidth narrower than the first beamwidth. For instance, theuser equipment 2202 may receive first signals in the first frequencyband 2402 transmitted using a beamwidth 2210. The first signals in thefirst frequency band 2402 may be comprised of signals and controlinformation that includes timing information, such as a framesynchronization parameter 2602, to synchronize timing of frames 2412,2416 of the communication systems 2240, 2250, respectively. The userequipment 2202 may use the first signals to facilitate detection andreceipt of second signals in the second frequency band 2402 transmittedusing a beamwidth 2220. The second beamwidth 2220 may be narrower thanthe first beamwidth 2210, thereby providing a potentially higher datarate relative to the wider first beamwidth 2210.

In one embodiment, the frame synchronizer module 2606 may retrievetiming information comprising a frame synchronization parameter 2602representing a frame synchronization period common to the firstcommunication system 2240 arranged for communicating information overthe first frequency band 2402 and the second communication system 2250arranged for communicating information over the second frequency band2404. The frame synchronization period 2418 may match a defined intervalof the second communication system 2250, such as a beacon interval ofthe second communication system 2250, for example. At the same time, theframe synchronization period 2418 may match a defined interval of thefirst communication system 2240, such as a multiple of a definedinterval of the first communication system 2240. In one embodiment, forexample, the frame synchronization period 2418 may evenly match one ormore frames 2412 (e.g., radio frames) of the first communication system2240.

At block 2708, the process 2700 includes activating a second receiver,such as the receiver portion of the transceiver 2318 as described withreference to FIG. 23. For instance, the frame synchronizer module 2606may receive the frame synchronization parameter 2602 as input, andoutput a control directive 2608 to activate the receiver circuitry 2388of the transceiver 2318 of the second radio module 2304.

At block 2710, the process 2700 includes receiving second signals in thesecond frequency band with the timing information. The second signalsmay be comprised of signals and control information to facilitate signaldetection, fine beamforming, CFO estimation, timing synchronization, andother information useful for allowing the user equipment 2202 to rapidlyestablish a communication channel with the base station 2208 of thesecond communication system 2250. In one embodiment, for example, thesecond signals may comprise one or more beacons 2502.

At block 2712, the process 2700 includes receiving third signals in thesecond frequency band. For instance, once the receiver circuitry 2388acquires and locks onto a beacon 2502, the receiver circuitry 2388 maybegin to receive third signals in the second frequency band 2404. Thethird signals may comprise the subsequent data or data signals to becommunicated (e.g., transmitted and/or received) using the secondfrequency band 2404, which may include signals for tracking of thebeamforming, CFO, timing, and so forth, as well as various types of dataincluding, for example, data relating to video streaming, realtimeand/or non-realtime collaboration, video content download, audio andtext content download and/or upload, and so forth. Alternatively, theuser equipment 2202 may start transmitting its own data via transmittercircuitry 2386 without (or before) receiving the third signals.

In various embodiments, the frame synchronizer module 2606 may utilizethe frame synchronization parameter 2602, which represents a framesynchronization period 2410, to synchronize communication frames 2412,2416 in the frequency bands 2402, 2404, respectively. In one embodiment,the frame synchronizer module 2606 may utilize the frame synchronizationparameter 2602 to synchronize with first time boundaries of firstcommunication frames 2412 in the first frequency band 2402 using theframe synchronization period. In one embodiment, the frame synchronizermodule 2606 may utilize the frame synchronization parameter 2602 todetermine second time boundaries of second communication frames 2416 inthe second frequency band 2404 using the first time boundaries of thefirst communication frames 2412. For instance, since the start timeboundary and the end time boundary of the first communication frames2412 are known, and the start time boundary and the end time boundary ofthe second communication frames 2416 are a known multiple of the size ofthe first communication frames 2412, the frame synchronization parameter2602 may predict or estimate a time when a beacon 2502 has beentransmitted in the second frequency band 2404. The frame synchronizermodule 2606 may issue a control directive 2608 to activate a receiver ofthe second radio module 2304 at or just before the estimated time toreceive second communication frames 2416 in the second frequency band2404 at one or more of the second time boundaries. The framesynchronizer module 2606 may issue a control directive 2608 todeactivate the receiver of the second radio module 2304 to conservepower at one or more of the second time boundaries.

Referring again to the control entity 2290, in addition to automaticallyand dynamically establishing a frame synchronization period 2410 tosynchronize frames between the communication systems 2240, 2250, thecontrol entity 2290 may establish different frame alignments signals fordifferent cells 2222. In this manner, the reliability of detection andacquisition in the mmWave band may be further improved by making mmWavepreambles specific for each mmWave cell, e.g., by making differentmmWave cells use different preambles. The information about the nearestmmWave cell (or set of cells) that user equipment 2202 can potentiallyassociate with is communicated to the user equipment 2202 in the lowerband. The user equipment 2202 uses this information to limit the numberof hypotheses when detecting preambles of beacon frames thus improvingthe detection performance and reducing power consumption. This may beespecially advantageous during the mmWave network entry or re-entryphase.

Although certain embodiments have been illustrated and described hereinfor purposes of description of the preferred embodiment, it will beappreciated by those of ordinary skill in the art that a wide variety ofalternate and/or equivalent embodiments or implementations calculated toachieve the same purposes may be substituted for the embodiments shownand described without departing from the scope of the presentdisclosure. Those with skill in the art will readily appreciate thatembodiments in accordance with the present disclosure may be implementedin a very wide variety of ways. This application is intended to coverany adaptations or variations of the embodiments discussed herein.Therefore, it is manifestly intended that embodiments in accordance withthe present disclosure be limited only by the claims and the equivalentsthereof.

1. An apparatus, comprising: receiver circuitry arranged to receivefirst signals in a first frequency band and second signals in a secondfrequency band, the first signals comprising a frame synchronizationparameter and the second signals comprising frame alignment signals; andprocessor circuitry coupled to the receiver circuitry, the processorcircuitry arranged to activate or deactivate the receiver circuitry toreceive the frame alignment signals based on the frame synchronizationparameter.
 2. The apparatus of claim 1, the processor circuitry arrangedto synchronize a frame in the first frequency band with a frame in thesecond frequency band based on the frame synchronization parameter. 3.The apparatus of claim 1, the frame synchronization parameter comprisinga reference time interval associated with a second beamwidth.
 4. Theapparatus of claim 1, the frame synchronization parameter comprising areference time interval associated with a second beamwidth, thereference time interval equally divisible by one or more frames of afirst communication system associated with a first beamwidth.
 5. Theapparatus of claim 1, the frame synchronization parameter comprising abeacon interval for a millimeter wave (mmWave) communication system, thebeacon interval equally divisible by one or more frames of a cellularcommunication system.
 6. The apparatus of claim 1, the processorcircuitry arranged to deactivate the receiver circuitry during a timeinterval defined by the frame synchronization parameter to conservepower.
 7. The apparatus of claim 1, the first signals in the firstfrequency band associated with a first beamwidth and second signals inthe second frequency band associated with a second beamwidth, wherein afirst beamwidth is broader than the second beamwidth.
 8. The apparatusof claim 1, the first signals in the first frequency band associatedwith a first beamwidth and second signals in the second frequency bandassociated with a second beamwidth, wherein a first beamwidth isassociated with a first communication system, and a second beamwidth isassociated with a second communication system.
 9. The apparatus of claim1, the first signals in the first frequency band associated with a firstbeamwidth and second signals in the second frequency band associatedwith a second beamwidth, wherein the first beamwidth is associated witha cellular communication system, and the second beamwidth is associatedwith a millimeter wave (mmWave) communication system.
 10. The apparatusof claim 1, the processor circuitry arranged to activate the receivercircuitry to receive third signals in the second frequency band, thethird signals comprising data.
 11. The apparatus of claim 1, theprocessor circuitry arranged to activate transmitter circuitry totransmit signals in the second frequency band after the second signalsare received.
 12. The apparatus of claim 1, the first frequency bandhaving a center frequency of less than 10 GHz, and the second frequencyband having a center frequency of more than 10 GHz.
 13. The apparatus ofclaim 1, the first frequency band comprising one or more frequencieswithin a 700 MHz to 2.5 GHz range, and the second frequency bandcomprising one or more frequencies within a 59 GHz to 62 GHz range. 14.The apparatus of claim 1, the first frequency band comprising one ormore frequencies within a 700 MHz to 2.5 GHz range, and the secondfrequency band comprising one or more frequencies within a 28 GHz to 31GHz range.
 15. The apparatus of claim 1, comprising one or moreradio-frequency (RF) antennas coupled to the receiver circuitry toreceive electromagnetic representations of the first and second signals.16. A method, comprising: receiving first signals in a first frequencyband associated with a first beamwidth; retrieving timing informationfrom the first signals, the timing information to indicate when todetect second signals in a second frequency band associated with asecond beamwidth narrower than the first beamwidth; receiving secondsignals in the second frequency band based on the timing information.17. The method of claim 16, comprising retrieving timing informationcomprising a frame synchronization period common to a firstcommunication system arranged for communicating information over thefirst frequency band and a second communication system arranged forcommunicating information over the second frequency band.
 18. The methodof claim 17, comprising retrieving a frame synchronization parameterthat matches a defined interval of the second communication system. 19.The method of claim 17, comprising retrieving a frame synchronizationparameter that matches a beacon interval of the second communicationsystem.
 20. The method of claim 17, comprising retrieving a framesynchronization parameter that matches a defined interval of the firstcommunication system.
 21. The method of claim 17, comprising retrievinga frame synchronization parameter that matches a multiple of a definedinterval of the first communication system.
 22. The method of claim 17,comprising retrieving a frame synchronization parameter that matches oneor more radio frames of the first communication system.
 23. The methodof claim 17, comprising synchronizing communication frames in the firstfrequency band and the second frequency band using the framesynchronization parameter.
 24. The method of claim 17, comprisingsynchronizing with first time boundaries of first communication framesin the first frequency band using the frame synchronization parameter.25. The method of claim 24, comprising determining second timeboundaries of second communication frames in the second frequency bandusing the first time boundaries of the first communication frames. 26.The method of claim 25, comprising activating a receiver to receivesecond communication frames in the second frequency band at one or moreof the second time boundaries.
 27. The method of claim 25, comprisingdeactivating a receiver to conserve power at one or more of the secondtime boundaries.
 28. At least one computer-readable storage mediumcomprising instructions that, when executed, cause a system to: retrievetiming information from signals received in a first frequency bandassociated with a first system, the timing information to indicate whento receive signals in a second frequency band associated with a secondsystem; and generate control information to activate or deactivate areceiver arranged to receive information in the second frequency bandbased on the timing information.
 29. The computer-readable storagemedium of claim 28, comprising instructions that when executed cause thesystem to retrieve timing information comprising a frame synchronizationperiod common to the first and second systems.
 30. The computer-readablestorage medium of claim 28, comprising instructions that when executedcause the system to retrieve a frame synchronization parameter thatmatches a defined interval of the second system.